How to find your bicycle tire size

How To Measure A Bike Wheel & Tire + Bike Wheel Size Chart

As you can imagine, wheels are an essential component of a bike.

Not only do bike wheels allow us to roll smoothly while cycling, but they also provide dampening from lumps and bumps as well as providing traction to the surface we’re riding. 

Many cyclists don’t understand how to measure a bicycle wheel, or how to measure a bike tire so I put together this bicycle wheel size guide to help you determine your current wheel size and what size bike tires you need for your wheels.  

Riding with wheels that are too big or small can cause damage to your bike, so pay attention to the steps below, and you won’t have any issues!

Ready to learn how to measure a bike wheel? Let’s hit the road.

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How to Measure a Bike Tire (How to Measure a Bicycle Tire)

Based on how much time you want to allocate to measuring your bike wheel, you can take a few different approaches.

You could attempt first to contact the manufacturer or the shop where you purchased your bike. Retailers and manufacturers have a record of all measurements and sizing information.

But be warned, retailers can be a nightmare to get hold of and often take a long time to reply. 

If you have a bike tire on your wheel, you can generally find required measurement information on the tire wall (side of tire – see picture below).

Tire walls usually display the size as determined by the European Tire and Rim Technical Organization, or ETRTO and will look something like the picture below. 

Bike tire wall size picture

If you can’t find the sizing on the wall of your tire, don’t panic. Below you’ll find several methods to help you understand how to measure your bike wheel. 

Alongside understanding more about your bicycle’s rim, a few of the methods below will also help you determine which tire size your wheel needs.

These steps are beneficial in those cases where you do not have a bike tire or have custom wheels, as the measurements you seek may not be readily available to you.

Typically there are two main approaches for how to measure bicycle wheel size. 

Just before we begin, if your wheel doesn’t have a tire fitted, click here to move on to the next step. 

The Standard Method (Easiest and Fastest Ways to Find Bike Tire Size)

The quickest way to determine your bike wheel size is the standard method.

The standard method measures the tire width and tire diameter in inches.

How to Measure Bike Wheel Size with the Standard Method

Let’s start with a step by step guide on completing the standard method of bike wheel measuring:

Bike Wheel RadiusBike Tire Width
  1. Begin by propping your bicycle on its kickstand or against a wall so that it’s stable.
  2. Using a tape measure, place the bottom of the tape at the lowest point of the tire (on the ground) and measure in a straight line to the centre of the bike wheel to find your wheel radius (as shown in the image above).
  3. Multiply your wheel’s radius by two to find the wheel’s diameter.
  4. Now, measure the tire’s width by placing the measuring tape across the top of it.
  5. The numbers obtained are your standard measurements. Be sure to list diameter first, followed by the tire width.
  6. Bike wheel diameters are rounded to the nearest half-inch, so if your measurements are just over or under, round up or down to the nearest size.

The ISO Method (Most Accurate Way to Measure Bike Tire Size)

The most accurate way to measure bike tire size is through the ISO method.

ISO stands for the International Organization for Standardization, a measuring system that uses millimetres to gain the most accurate sizing possible for a bike tire. 

Using this method, one measures the width of the tire and the inner diameter, or bead seat diameter.

Towards the end of the article, you’ll find a chart allowing you to compare the different ISO wheel sizes and what types of bike or vehicle each size of wheel is used with. Click here to view the chart.  

How To Measure Bike Tire with the ISO Method

Here is a step by step guide on how to measure a bike tire using the ISO standardization method. 

  1. Not all wheel brands and manufacturers use the ISO standardization, so if you have a tire on your wheel, check it to see if there is a printed ISO measurement. 
  2. If there is no visible ISO measurement on your tire, check the wheel rim.
  3. If you can’t find a measurement, lean your bicycle against the wall or with its kickstand so that it’s stable.
  4. With a measuring tape, begin at the centre of the wheel and measure up to the tire’s inner edge (or as close to the bead seat as possible).
  5. If you don’t have a tape measure with millimetre readings, measure in inches and multiply it by 25.4 (for example, 12.25(inches) x 25.4 = 311mm).
  6. Identify this length and multiply it by two for the diameter of your wheel (311 x 2 = 622mm).
  7. Measure the tire’s width by measuring from one side of the tire to the other.
  8. You now have all of the calculations needed for the ISO method. This measurement is listed with the tire’s width first, then the diameter (25-622).

How To Measure a Bike Wheel (Rim) for Tire Size

If you do not have your bike’s tire to hand, you can determine the tire size by measuring your bike’s rim width in millimetres as well.

Based on the average tire and wheel combinations currently on the market, the following charts illustrate the coinciding tire size and rim length.

This bike wheel has an ISO 622mm with an internal bead seat width of 15mm. Not all wheels will display their measurments!

Many rims will display their size somewhere, but some rims may be missing this measurement. 

If you cant find. measurement on your wheel’s rim, follow the easy steps below that will help you determine the appropriate tire sizes your rim can handle.

  1. With no tire on your bike wheel, position the wheel vertically and hold it steady.  
  2. Take a measuring tape and press it against the inside of the rim, where the tire bead would normally sit.
  3. Measure the internal distance from one side of the rim to the other (as shown in the image above).
  4. Take this width and apply it to the correct table below.

It’s important to note that these charts are based on average measurements; therefore, if possible it’s a good idea to double-check with your wheel’s manufacturer or retailer to confirm all compatible tire sizes.

It’s also important to consider the tire clearance on your fork and rear triangle. If you choose a tire that’s too wide you can end up damaging your frame and a tire that’s too thin can easily cause damage to your rim and inner tube.

Road Bike Rim Width to Tire Size Chart

Tire Size Compatibility Internal Rim Width
23 - 25c 13-15, 17-19mm
25 - 28c 13-15, 17-19, 20-21, 22-23mm
30 - 33c 17-19, 20-21, 22-23, 24-25mm
33 - 35c 17-19, 20-21, 22-23, 24-25mm
38 - 40c 20-21, 22-23, 24-25mm
40 - 43c 20-21, 22-23, 24-25mm
43 - 45c 22-23, 24-25mm
45 - 48c 22-23, 24-25mm
48 - 50c 24-25mm

Mountain Bike Rim Width to Tire Size Chart

Tire Size Compatibility Internal Rim Width
1. 9" Tires 19-23mm
2.0" Tires 19-24mm
2.1" Tires 19-28mm
2.2" Tires 20-30mm
2.3" Tires 21-33mm
2.4" Tires 23-34mm
2.5-2.7" Tires 25-35mm
2.8-3.1" (plus) Tires 22-23, 24-25mm

How to Measure Kid's Bike Wheels

The process of measuring a kid’s bike wheel and tire size follows similar steps to those shown above, but kid’s bike tires are measured in inches and are understandably smaller than those of an adult bike.  

I’ve put together a simple guide for everything to do with kid’s bike sizing.

If you’re looking to measure the wheels on a kid’s bike, or are looking to determine which size bike is best for your kid, have a read of this guide, which includes all of the bike and wheel size charts you’ll need!

Follow the steps within this guide closely, as a poor fitting kids bike can put you child off cycling for good.

Measure Bike Wheel Circumference for a Bike Computer

Measuring your wheel’s circumference for a bike computer is an important task that will determine the accuracy of the data your computer provides.

To simplify the steps required to measure your wheel’s circumference for a cyclometer, I’ve put together a simple bike wheel circumference guide. 

These three simple methods will help you accurately measure your wheel’s circumference.

You won’t need any specialist equipment, apart from a measuring tape. 

This may look interesting, but it's one of the easiest ways to measure the circumference of a bike wheel for a bicycle computer!

Most Common Bike Wheel Sizes

Each type of road bike and mountain bike comes with a different set of average wheel sizes. In general, each of these sizes offer a unique set of benefits and drawbacks.

What Is the Most Common Road Bike Wheel Size?

The most common size wheel for a road bike is 700c, and has been the standard size for a number of years.

The 700 refers to the wheel’s diameter of 700 mm, while the “c” is an old French width code for tires.

With “a” characterized as the most narrow width and “d” at the widest, “c” refers to a generally wider size.

Most Common Size of Mountain Bike Wheel

Mountain bike wheels come in three main sizes: 26 inches/559 wheels, 27.5 inches/650b wheels, and 29 inches/622 wheels.

The smaller, 26-inch mountain bike wheels were once considered standard size and are more lightweight and agile than larger sized wheels.

Despite their popularity in the past, 26-inch wheels are no longer the standard, as larger wheels have a better grip, traction, and durability and have therefore become more popular.

Both the 27. 5-inch and 29-inch wheels offer a smoother and more controlled ride while sacrificing some of the acceleration capabilities of a 26-incher.

ISO Wheel Size Chart For Bike Tires and Rims

ISO otherwise known as the International Organization for Standardization developed the ISO wheel size system, which is universal and simplifies the once confusing task of finding the right size wheel for your bike. 

The ISO standardization system uses two different numbers, that can often be found printed on the tire or rim walls.

The second number displayed in ISO tire size is the important one and represents the wheel’s bead seat diameter (as shown in the ISO size chart below).

If your wheel rim or tire has no size markings, you can use this ISO wheel size chart after measuring your wheels, to cross-reference and understand more about the size of your bike’s wheels.

ISO Bead Seat Diameter Traditional Sizings Applications
137mm 5. 4" 8 x 11/4 Wheelchairs
152mm 6" 10 x 2 Wheelchairs
203mm 8" 12 1/2 x various Scooters (children's)
254mm 10" 14 x 2.00 Various (children's)
305mm 12" 16 x 1.75 - 16 x 2.125 Folding bikes, some recumbents
317mm 12. 5" 16 x 1 3/4 Schwinn (children's)
337mm 13.25" 16 x 1 3/8 Very rare bike tire
340mm 13.4" 400 A Folding bikes, European bikes (children's)
349mm 13.75" 16 x 1 3/8 Folding bikes, recumbents, bikes (children's)
355mm 14" 18 x 1.5 - x 2.125 Folding bikes, bikes (childrens)
369mm 14. 5" 17 x 1 1/4 Moulton bikes
390mm 15.35" 450 A European bikes ( children's)
406mm 16" 20 x 1.5 - x 2.125 BMX, bikes (children's), folding bikes, recumbents
419mm 16.5" 20 x 1 3/4 Schwinn (children's)
440mm 17.3" 500A European bikes (children's), folding bikes
451mm 17. 75" 20 x 1 1/8; x 1 1/4; x 1 3/8 Bikes (children's), BMX, recumbents, folding bikes
457mm 18" 22 x 1.75; x 2.125 Bikes (children's)
490mm 19.3" 550 A European road bikes (children's)
501mm 19.75" 22 x 1 3/8, 22 x 1.00 British bikes (children's)
507mm 20" 24 x 1.5- x 2.125 Mountain bikes (children's), cruisers
520mm 20. 5" 24 x 1, 24 x 1 1/8, 24 x 1 3/4 Schwinn bikes
540mm 21.25" 24 x 1 1/8, 24 x 1 3/8 (E.5), British bikes (children's), wheelchairs, Japanese women's bikes
547mm 21.5" 24 x 1 1/4, 24 x 1 3/8 (S-5) British bikes (children's), Schwinn bikes (children's)
559mm 22" 26 x 1.00- x 2.125, fatbike tires up to 5 inches wide Mountain bikes, cruisers, fatbikes, Schwinn bikes
571mm 22. 5" 26 x 1, 26 x 1 3/4, 650 C Cannondale bikes, wheels for shorter cyclists, Schwinn bikes
583mm 22.95" 700 D GT bikes
584mm 23" 650B, 26 x 1 1/2, 27.5 French bikes, tandem and touring bikes, Raleigh & Schwinn mountain bikes
590mm 23.25" 26 x 1 3/8 (E.A.3), 650 A French & Italian bikes, English 3 speed bikes
597mm 23. 5" 26 x 1 1/4, 26 x 1 3/8 (S-6) British bikes, Schwinn bikes
599mm 23.6" 26 x 1.25, x 1.375 Old US bikes
622mm 24.5" 700 C, 28 x 1 5/8 x 1 1/2, 29 inch, 28 x 1 1/2 F.13 All bike types, Canadian bikes (F.13),
630mm 24.8" 27 x anything (not 27.5), 609mm Rare Danish bikes, old road bikes
635mm 25" 28 x 1 1/2, 700 B, 28 x 1 5/8 x 1 1/2 European roadsters, old Swedish bikes
686mm 27" 32 inch Unicycles, Custom bikes
787mm 31" 36 inch Unicycles, Custom bikes

Bike Wheel FAQs

How do you remove a bike wheel?

The process of removing a bike wheel varies based on whether you wish to remove the front or back wheel.

Remove the front wheel by releasing the brake, flipping the bike over, opening its quick-release or unscrewing the wheel nuts, and pulling it off the fork.

Remove the back wheel by shifting the chain down onto the smallest cog, opening the break, loosening your quick release or wheel nuts, then pull the rear derailleur back and remove the wheel at the same time. 

Are bike wheels universal?

Bike wheels are not universal.

As bikes come in many different sizes, you’re limited with what size wheels you can use with a bike.

Usually, you’ll be able to make minor adjustments to the size of your wheels or tires, but wheels that are too big or small can easily damage your bicycle. 

Can you put a road bike wheel on a mountain bike?

Putting road bike wheels on a mountain bike frame can be done and is a popular option for many commuters who cycle to work in the city but switch back to MTB wheels to hit the trails.

Just remember, as the designs of road and mountain bike wheels vary drastically, you’ll probably need to make adjustments elsewhere on your bike!

But yes, putting road bike wheels on a mountain bike is entirely possible!

Can you put a mountain bike wheel on a road bike?

For improved aerodynamics, the frame of a road bike is typically narrower and offers less wheel clearance than a mountain bike.

Due to the reduced wheel clearance road bikes typically offer, the wider tires and wheels that accompany a mountain bike are not usually compatible with road bike frames. 

That being said, some slimmer 29-inch mountain bike wheels with narrow ties may fit on a road bike that takes 700c wheels. 

However, cycling with wheels that are too big can end up causing damage to your bicycle. 

If in doubt, don’t risk it.

Conclusion - How To Measure a Bike Wheel

I hope you found the content within this short article helpful. You should now understand exactly how to measure a bike wheel and how to measure a bike rim for a tire. 

If I’ve left any of your questions unanswered, leave me a comment down below and I’ll get back to you straight away.

As always, make sure to use a good quality bike lock to secure your bike, when leaving it unattended.

If you’ve been wondering which size bike frame fits you best, have a read of this short guide, which will help you select the most suitable bike size in a few quick steps.  

Lock it or lose it.

Ciao for now.

Author of This Post:

How to Measure Bike Tire Size

Your bike tire size isn’t just a number on a spec sheet or the tire’s sidewall, it’s an important part of your bike setup. Your tire’s diameter and width play a big role in how your bike handles and feels, how fast it rolls, and how well it grips the road or trail underneath. It’s an important bit of info to know, especially when it comes time to replace your tires, or if you’re looking to test out different sizing.

Generally, the larger the tire and wheel is in diameter, the faster you’ll roll, and the easier it’ll be to roll over obstacles. But smaller wheels may be preferred by some for height or maneuverability reasons. Similarly, the narrower the tire, the faster it rolls—plus it’s lighter—while a wider tire will offer greater traction and stability. Below, we explain bike tire sizes, tire styles, rider height, and more.

Get Bicycling All Access for the latest cycling and repair tips!

How do I know my bike tire size?

Bike tires come in all sorts of sizes, but it should be really, really easy to determine the size of yours. If you’re looking to purchase a replacement tire, simply look along the sidewall of your current tire (check both sides). You’ll see something printed like “700x25mm” or “29x2.30”—that’s your tire size.

The tire is marked with the size and recommended pressure.

Trevor Raab

You’ll also see the make and model of the tire, along with the recommended psi range for inflating your tire. Knowing how to measure your bike tire size is handy, but technically you shouldn’t need to measure anything in most circumstances because sizing is printed right on the tire.

What do bike tire size numbers mean?

Road, Gravel, and More

The first number refers to the diameter of your tire. The “700” that you will commonly see as the first number—especially on road bikes, gravel bikes, fixies, and more—denotes a 700-millimeter wide diameter tire. Another somewhat common size is 650mm, which is typically found on smaller adult bikes.

Accordingly, the second number refers to the metric width of the tire. Common widths for metric-based bike tires run anywhere from 23mm to as much as 48mm, or even more as gravel tires get increasingly wider.

Furthermore, you may see metric sizing listed as 700c or 650b. This is the older standard for sizing, where different letters represented different tire bead seat diameters. You will also see ISO sizing for tires, which is a more precise measurement for the tire bead seat diameter, though you usually won’t need to worry about it when picking out tires. For example, the ISO size of 622 corresponds with 700-size tires.

What’s a tire bead? Tire beads are the inner edges of the tire. They’re rounded and fit into the wheel rim to lock the tire into place once it’s inflated. A tire bead is said to be “seated” when it’s properly locked into place with the rim.

Mountain, Kid’s, and Fat Bikes

A significantly smaller first tire size number, like 29 or 26, means the tire diameter is sized in inches. This sizing is common for mountain bikes, kid’s bikes, fat bikes, and some hybrids. Modern mountain bike tires are now either 29 inches or 27.5 inches in diameter; 26 inches is the older standard, though many of those bikes are still in use. Fat bike tires are typically either 27.5 or 26 inches. Kid’s bike tires are usually anywhere from 12 to 26 inches.

Trevor Raab

Trevor Raab

The second number for tire width with this sizing is also listed in inches. Common mountain bike tire widths now range from 1.85 to 2.6 inches. Plus-size tires (sometimes called mid-fats) for mountain bikes are wider than typical mountain bike tires, but aren’t quite fat tires; they range from 2. 8- to 3-inches wide. Actual fat bike tires require different (wider) rims. You’ll typically see fat bike tire widths range from 3 to 5.2 inches, and you may see their metric size listed as well.

4 Flat Tire Fixes
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How to measure bike tire or wheel size

In the event that the size has worn off of the side of your tire (it likely won’t), you could use a caliper or tape measure to measure tire width and diameter. Or, if the bike has no tires to begin with, you can measure your wheel rim diameter—in the middle of the wheel from end to end—as a starting point. You could also look up or contact the bike or wheel manufacturer to see which tire(s) will be compatible.

How to measure bike tires or wheels for height

With adult bicycles, there are a few wheel size options, but it’s best to get a bike that’s sized to fit you well overall, as the frame size is more crucial to proper bike fit. Each bike company will have a size chart you can reference. Some bike companies do offer two wheel size options during purchasing, typically on smaller sized bikes, and that’s when you may need to decide between bike wheel sizes.

You may be able to put smaller wheels on a bike, depending on your frame and your brakes; rim brakes may not line up properly with a different size wheel. But you may also need to make other modifications (like crank length, for pedal clearance reasons). It’s often better, and easier, to have the right size bike from the start.

How to measure bike wheel size for kids

Related Story
  • The Best Kids’ Bikes to Buy Right Now

Kid’s bicycles, on the other hand, have a much wider range of tire sizes in order to accommodate a variety of heights. When you’re looking to purchase a new kid’s bike, the wheel size will correspond with the overall bike size, so it’s best to reference the bike manufacturer’s size chart. For example, the company Woom offers kid’s bikes in six different sizes and uses both height and inseam to help customers determine the right size bike and wheel combination.

Can I put wider tires on my bike?

A 28mm tire vs a 30mm tire, in the same fork.

Trevor Raab

You likely can, but there’s a limited range of tire-width compatibility for each bike. How wide you can go will depend on how much clearance you have with the tire installed between the fork arms, seatstays (or frame in general), and brakes (unless you have disc brakes). Beyond that, it’ll also depend on your wheel rims.

What type of bike tires do I need?

Here are the different styles you may encounter in your quest for new bike tires.

Charlie Layton

Clincher: This is the most common type of bike tire on the market now. Clincher tires use inner tubes to stay inflated and tire beads to attach to the rim. Inner tubes are not one-size-fits-all—you’ll need a tube that matches your tire diameter and width.

Tubeless: Tubeless tires are the newest style of bike tire. As its name suggests, tubeless tires don’t use inner tubes to stay inflated. Instead, they use tire sealant to create an airtight seal around the tire bead once inflated. If you’d like to convert to tubeless tires, you’ll need tubeless-compatible wheel rims.

Related Story
  • A Step-by-Step Guide on How to Fix a Flat Tire

Tubular: An older style of bike tire where the tire is glued to the rim. It’s less common now but is still utilized by some, including some pro road racers and cyclocross riders.

Beyond that, there are a variety of treads available for different sizes. Consider the kind of riding you usually do—do you ride pavement, gravel, both? A tire with more tread will offer better grip and is well suited for a variety of terrain, while a tire with little to no tread (like on many road bikes) will have less rolling resistance and will enable you to go faster.

And remember, when in doubt, your local bike shop is the best resource you have for figuring out all of your bike tire—and other bike—needs.

Jessica Coulon

Service and News Editor

When she’s not out riding her mountain bike, Jessica is an editor for Popular Mechanics. She was previously an editor for Bicycling magazine. 

How to choose the size of a bicycle tire. What types of markings and interchangeability of bicycle tires.

How to choose the size of a bicycle tire. What types of markings and interchangeability of bicycle tires.

Nikolaev bicycle shop "Sportek"

Published: 01/27/2017

Edited: 06/01/2021

Sooner or later, almost every cyclist faces the question of replacing the rubber on the wheel or the cameras for them.

The easiest way, of course, is to look at the size of the tire currently installed on the bike (it is written on the side of it), and look for exactly the same. On some rims, their landing diameter and width are also written.

In life, everything is always a little more complicated and it often happens that the tire you like has a marking that is not entirely clear or does not match the marking on your rubber. Sometimes it is necessary to replace the old bicycle rubber, which has served for many years, with a more modern one.

What to do? You can’t put a tire on a bike over the Internet, but you don’t want to pay money just like that.

In this article, we will try to help you understand the markings on bicycle tires and find out which of them are interchangeable.

The following questions will be considered in the article:

  • bicycle wheel sizes;
  • types of bicycle tire markings;
  • interchangeability of bicycle tires in terms of fit diameter and width.
  • selection of tire width from rim width

Wheel dimensions or more precisely rim dimensions

The first thing you need to know when choosing a tire is the size of the wheels. They are usually measured in inches, but sometimes in mm. There are not very many of them and the most common are 16, 18, 20, 24, 26, 27.5, 28, 29.

At the same time:

  • 16, 18, 20 - installed on children's bicycles;
  • 20, 24 - for teenagers
  • 26 - for mountain and downhill bikes
  • 26 and above - for adult models.

Further, what else you need to know is seat size (diameter) of the rim or BSD (English Bead Seat Diameter). It is the most important and determines the interchangeability of tires. If this number matches at the rim, tire, or tube, then that tire or tube fits those rims. And if the width of the new rubber can be changed, then the landing size will not change much.

If the size (numbers in mm) is written on the wheel (rim), for example, as in the photos above, they accurately indicate the fit size of the rim and its width, which is the main data for selecting the inner tube and tire for the wheel.

Bicycle tire label

There are several types. The confusion in the designation of sizes began in the middle of the 20th century, and today Great Britain and France use their own designations for marking.

Previously, the sizing system was based on the outside diameter of the tires. It was measured in inches (24", 26", 28") or in millimeters (500, 650, 700, etc.).

Over time, this system lost its meaning, because different products with the same outer diameter wheels (together with the height of the tire) did not match the inner diameter (rim diameter) on which this tire was put on.There were also marketing moves of manufacturers, and the accuracy of translation and rounding of measurements in inches is lower than in millimeters.0003

To overcome these confusions and bring all sizes to the same standard, the International Organization for Standardization (ISO - International Organization for Standardization) has developed a universal system for designating tire sizes - ISO 5775 . This system was previously known as " ETRTO ". It was proposed by the organization of the same name: ETRTO (European Tire and Rim Technical Organization or in Russian: "European technical organization for rims and tires").

Types of markings for bicycle tires:

  1. Marking according to ISO specifications (ETRTO). The most accurate, understandable and convenient. Describes in millimeters all the necessary dimensions. For example, 28-622, where 28 mm is its width and 622 mm is inner (landing) diameter .
  2. Fractional marking in inches, type 28x1 1/8. Where: 28 is the outer diameter in inches and 1 1/8 is its width in inches (one whole and one eighth of an inch).
  3. Marking in inches in decimal fraction. For example: 26x1.75. Similarly: 26 - is the outer diameter of in inches, and 1.75 is the width. What is the difference between simple and decimal fractions in these notations, and what problems does this bring, we will talk a little lower.
  4. Designation of dimensions in the form of several numbers in inches: 28 x 1 5/8 x 1 3/8. Where: 28 - is the outer diameter of in inches, 1 5/8 is the height of the bike tire in inches (one whole and five eighths of an inch), 1 3/8 is its width in inches (one whole and three eighths of an inch).
  5. French mark. In our country, it is less common, however, on wheels made in Europe or for Europe, it is often applied.

    At first it was in the form of a number and a letter, for example, 700C - 700 the outer diameter of the tire is in mm. The letter determined the width from "A" - the narrowest to "D" - the widest.

    Now the marking has acquired a more modern look. For example: 700 x 35C. Here the outer diameter of the tire is 700 mm and its width is 35 mm. The letter at the end indicates the inner (landing) diameter. In this case, "C" is 622 mm.

  6. On the old Soviet bicycle tires, the marking was also in millimeters, but it looked like 533x37. Those. first inner diameter tire (rim size ) - 533 mm, and then its width - 37 mm. (instruction for Soviet bicycles: "SPORT", "Salyut")

The problem of decimal and fractional tire sizes in inches

Note a very important nuance and paradox in inch sizes. Tire sizes can be specified as a decimal fraction, such as 26x1.75, or as a simple fraction, such as 26x1 3/4.

Mathematically, these fractions are equal: 1.75 = 1 3/4.

But, in terms of fit size and tire width in millimeters, this is not always the case, and the most unpleasant thing is that tires with such dimensions can be not interchangeable with .

And this circumstance should always be taken into account when purchasing a new bicycle tire.

Table of interchangeability (compatibility) and ratios of tire sizes in different marking systems

In the table below, we have tried to collect the most common tire size designations in different systems and show their compatibility.

Perhaps not all dimensions encountered in life were taken into account, but if you have a tire with dimensions not listed in the table, try to estimate its dimensions based on similar nearest or similar dimensions.

Rim bore size
in mm according to ISO
Tire size
in plain and decimal inches
French tire size Tire size
in mm according to ISO
(width - bore)
681 22-681 Sports track bike B-64 "Record" KhVZ (1958)
642 28 x 1 5/8 x 1 1/2 700-28A 28-642 Obsolete size
28 x 1 3/8 700-35A 37-642
635 28 x 1 1/2 x 1 1/8 700-28B 32-635 American, English, Danish, Chinese, Indian road models
28 x 1 1/2,
28 x 1 1/2 x 1 5/8
700B Standard
28 x 1 5/8 x 1 1/2 44-635
630 27 x 7/8 22-630 Road bikes, including older models
27 x 1 25-630
27 x 1 1/8 28-630
27 x 1 1/4 32-630
27 x 1 3/8 37-630
27 x all options
622 29 x all variants 700C This size was invented by marketers for tires with a bore diameter of 622 mm. They differ from 28 only in tire height.
28 x decimal 700C For 622 mm tires
28 x 3/4 700-18C
28 x 3/4 700-20C
28 x 1
28 x 7/8
28 x 1 700-25C
28 x 1 1/8,
28 x 1 5/8 x 1 1/8
28 x 1.20 700-30C
28 x 1 3/4,
28 x 1.5
40-622 Road bikes: "Ukraine", "Minsk", "Sura", "Velta", "Aist" (111-321, 111-322)
28 x 1 1/2,
28 x 1 5/8 x 1 3/8


Road bikes: "Ukraine", "Minsk", "Sura", "Velta", "Aist"
27 x 1 1/4,
28 x 1 5/8 x 1 1/4
32-622 Road and sports touring bikes, "Tourist", "Sport", "Sputnik"
28 x 1 5/8 x 1 1/4 Obsolete Canadian designation F13
28 x 1. 4 700-35C
35-622 Road bikes
28 x 1.5 700x38C
28 x 1 3/8 x 1 5/8 37-622
28 x 1.6 700-42C
28 x 1.6 700-44C
28 x 1 5/8 x 1 3/4 700-45C
28 x 1.75,
28 x 1 5/8 x 1 3/4
28 x 2.00 700-50C
600 22 (23, 24, 25, 27, 28, 30)-600 Old Soviet sports and track bikes
599 26 x 1.25,
26 x 1.375
32-599 Very old American light bicycles.
26 x 1 7/8 47-599 ZiF (Penza) 190-535 "Samson"
597 26 x 1 1/4 (EA1) (England) 32-597 English old sports and club bikes.
26 x 1 3/8 (S-6) 37-597 Light bicycles of the American firm Schwinn.
590 26 x 1 1/8 28-590

Soviet bicycles ZiF (Penza)

"Diana", "Prima", "Turn", "Relay", "Sura", "Breeze", "Temp"

American and English 3 and 10 speed.

26 x 1 1/4 32-590
26 x 1 3/8 (E.A.3) (England) 650A 35-590
26 x 1 3/8 650-35A
26 x 1 5/8 44-590
587 700D Old size on some GT models
584 27. 5 x 1.50 650x38B 40-584 French road bikes, touring bikes with cargo, tandems, some Raleigh (USA), old Schwinn mountain bikes
26 x 1 1/2 650B 37-584
27.5 x 1.5 40-584
27.5 x 1.65 44-584
27.5 x 1.75 47-584
27.5 x 2 52-584
27.5 x 2.1 54-584
27.5 x 2.25 57-584
27.5 x 2.3 60-584
27.5 x 2.4 62-584
27.5 x 2.8 70-584
571 26 x 3/4 650x20C 20-571 Triathlon, time trial, small road bikes, some French Peugeot bikes.
26 x 7/8 650x23C 23-571
26 x 1 650C 23-571
26 x 1. 75 47-571
26x1 3/4 (S-7) Road Schwinn
559 26 x 1.0 25-559 Most mountain bikes. Classic landing diameter for 26 wheels.
26 x 1.25 32-559
26 x 1.35 35-559
26 x 1.4 37-559
26 x 1.5 40-559
26 x 1.6 44-559
26 x 1.75
26 x 1.75 x 2
26 x 1.95 50-559
26 x 2.00 52-559
26 x 2.10 54-559
26x2.15 55-559
26 x 2. 25 57-559
26 x 2.3 60-559
26 x 2.4 62-559
26 x 3.0 75-559
26x3.7 95-559
26 x 4.00 100-559
26x4.5 115-559
26x4.8 120-559
547 24x1 1/4 English children's and American firm Schwinn
24x1 3/8 (S-5) Schwinn American children's bicycles
540 24 x 1 1/8 600A 28-540 Children's English and European bicycles, most wheelchairs
24 x 1 1/4 32-540
24 x 1 3/8(E-5),
24 x 1 3/8 A
533 24 x 1 1/2 37-533

"Salute", "Altair", "Ervi", "Eaglet", "Erelyukas", "Swallow" ("Kregzdute", "Kregzhdute" - Siauliai bicycle factory "Vairas" Lithuania).
This is the Soviet standard and tires with a diameter of 533 mm are available only with a width of 37 mm.

Be careful when replacing as not all 24" tires will fit 533 wheels.

531 24 x 1 5/8 x 1 1/2 44-531
520 24x1 25-520 Road wheels for children's bikes
507 24 x 1.5 40-507 Children's mountain. "Salute", "Altair", "Ervi"
24 x 1.75 47-507
24 x 1.95 50-507
24 x 2.0 51-507
24 x 2.125 54-507
24 x 2.25 57-507
24 x 2.35 60-507
24 x 2. 5 62-507
24 x 2.6 65-507
24 x 2.75 70-507
24 x 3.0 75-507
501 22 x 1.0 25-501 European bikes
22 x 1 1/4 32-501
22 x 1 3/8 37-501
490 550-28A 28-490 European Road Kids Bikes
22 x 1 3/8 x 1 1/4 550-32A 32-490
22 x 1 3/8 550-35A 37-490
489 22 x 1.0 25-489 European bikes
22 x 1 3/8 37-489
22 x 1 3/8 x 1 1/4 40-489
22 x 2. 00 50-489
457 22 x 1.75 to 2.125 Children's bicycles
451 20 x 1 1/8 28-451 BMX for light riders, light children's bikes, some ligerades.
Wheels on some types of wheelchairs.
20 x 1 1/4 30-451
20 x 1 3/8 37-451
445 20 x 1 1/4 30-445 "Schoolboy" (old Soviet models)
440 500-28A 28-440 European folding, children's bikes
500-35A 37-440
20 x 1 1/2 500-38A 40-440
438 20 x 1 3/8 37-438 European bikes
20 x 1 3/8 1 1/2 40-438
432 20 x 2 1/2 40-432 European bikes
428 20 x 2. 00 54-428 European bikes
419 20 x 1 3/4 Schwinn American children's bicycles
406 20 x 1.25 32-406

Most BMX bikes, kids and folding models.

"Venta" (folding model 175-811).

"Stork" (folding, model 113-322)

"Tisa-2", "Cross", "KAMA", "DESNA", "Schoolnik", "Velta Kama", "Dubisa" (Siauliai bicycle factory), "Eureka" and other folding and old Soviet models.

Folding "Mustang"

20 x 1.35 35-406
20 x 1 3/4
20 x 1.5
20 x 1.75,
20 x 1.75 x 2
20 x 1.95 50-406
20 x 2.00 54-406
20 x 2. 125 57-406
20 x 2.35 60-406
20 x 2.5 62-406
20 x 2.6 65-406
20 x 2.75 70-406
20 x 3.0 75-406
390 18 x 1 1/8 450-28A 28-390 Children's European bikes
18 x 1 3/8 450-35A 37-390
450-55A 55-390
387 18 x 1 1/2 37-387 Children's European bikes
369 17 x 1 1/4 32-369 Bicycles Alex Moulton
355 18 x 1 1/8 28-355 Children's bicycles
18 x 1. 25 32-355
18 x 1.35 35-355
18 x 1.5 40-355 Birdy folding bikes.
18 x 1.6 42-355 Children's bicycles
18 x 1.75 47-355
18 x 1.95 50-355
18 x 2.0 54-355
18 x 2.125 57-355
349 16 x 1 1/8 28-349 Old Moulton, Brompton and other folding bicycles, ligerade front wheels, children's bicycles.
16 x 1 1/4
16 x 1.25
16 x 1.35 35-349
16 x 1 3/8 37-349
340 400-30A 28-340 Children's European bikes
16 x 1 3/8 x 1 1/4 400-32A 32-340
16 x 1 3/8 400-35A 37-340
16 x 1 5/8 400A 44-340
335 16 x 1 3/8 Children's Polish bicycles
330 16 x 1 1/2 400-38B 40-330 Children's bicycles
317 16 x 1 3/4 Schwinn American children's bicycles
305 16 x 1. 5 40-305 Children's bicycles, folding, touring and some ligerades.
16 x 1.75 47-305
16 x 1.95 50-305
16 x 2.0 54-305
16 x 2.125 57-305
16 x 2.5 62-305
298 14 x 1 1/4 350-32A 32-298 Carriages, children's bikes, balance bikes
288 14 x 1 3/8 350A,
37-288 Children's bicycles, balance bikes
14 x 1 5/8 350-38A 40-288
14 x 1 5/8 x 1 3/8 350-42A 44-288
14 x 1.75 47-288
279 14 x 1 1/2 350-38B 40-279 Children's bicycles, balance bikes
254 14 x 1. 5 40-254 Children's bicycles, balance bikes
14 x 1.75 47-254
14 x 2 54-254
239 12 1/2 x 1 3/8 x 1 1/4 300-32A
32-239 Children's bicycles, balance bikes
205 12 1/2 x 2 1/4 56-205 Children's bicycles "KVD", balance bikes, sometimes suitable for baby carriages ("Dutik" tires)
203 12 x 1.75
12 1/2 x 1.75
12 1/2 x 1.9
47-203 Small children's bicycles, balance bikes, baby carriages
12 x 1.95 54-203
12 x 2.0 50-203
12 x 2.125,
12 1/2 x 2 1/4 R
12 1/2 x 2 1/4 62-203
176 55-176 Tires for tricycles, scooters, balance bikes for small children, wheelbarrows and carts, prams
152 10 x 2 54-152
137 8 x 1 1/4 32-137

In short, we can say that adult bikes have a seat diameter for:

  • 28 and 29 wheels - 622 mm. 29 tires differ from 28 only in height.
  • 27.5 inches - 584 and 590 mm. For these wheels, you need to be careful when choosing rubber, since both landing diameters fit them and often the size “26 x …” is written on tires suitable for these wheels.
  • 26" - 559 mm

Small but interesting nuances regarding tire width:

  1. Tire width written on it does not always coincide with its actual width. In most cases, it depends on the pressure in it and the methods of measuring the width, especially on studded tires.
  2. Moreover, it sometimes does not coincide with mathematics. For example, a width of 2.125 inches is 54 mm (2.125 * 25.4 = 53.98 mm), but manufacturers, especially Chinese ones, stubbornly write 57 mm on it, although this applies more to a width of 2.25 inches.
  3. That is why, relative to the width written on the tire, calmly, and not with accounting accuracy.

How to choose the right bicycle tire width

Tire width selection is more flexible than rim diameter.

Rim widths are measured and marked in millimeters as shown in the figure at the beginning of the article.

How to measure the width of the rim is described in a separate article here.

Dependence of tire width on rim width for different types of bicycles:

Rim width
in mm
Tire width
in mm and inches
Bicycle type
13 18 - 25 mm (1") road and cyclocross models
15 23 - 32 mm (1" - 1.25")
17 25-37 mm (1" - 1.5") light cross-country and hybrid models
18 28 - 44 mm (1.1" - 1.75") heavy cross-country and hybrid models
19 28 - 60 mm (1.1" - 2.35") MTB (mountain bikes, mountain bikes)
20 28 -47 mm (1. 1" - 2") cycling and light extreme
21 35 - 50 mm (1.4" - 2")
23 40 - 50 mm (1.5" - 2.1") extreme cycling
25 or more 44 - 57 mm (1.75" - 2.25")
32 75 mm (3") and over

This table shows guide data for a medium bike. Use it not as a dogma, but as a guideline for selection.

Some manufacturers give their own tables for the tires they produce, according to which they need to be selected for their wheel.

If the tire is narrower than the rim:

  • the chance of punctures is much higher
  • rims can be damaged

If the tire is much wider than the rim:

  • Poor handling at low speed.
  • Tires wear out faster - especially the sidewall.
  • Even with a slightly inflated tire, the handling of the bike is greatly impaired.
  • The possibility of it breaking off the wheel rim during a sharp turn increases.

The tire width affects rolling and grip. The wider - the better the grip, cornering control, but the worse the roll.

It is considered optimal if the width of the tire is 1.5-2.1 times wider than the inner width of the rim. It is possible and 2.5 times, but this is already an amateur.

The tire-to-rim width ratio affects the tire's cornering behavior. Too wide tires mounted on a narrow rim can simply break. will have a pear-shaped profile.

Further, if the wheel is equipped with toothy rubber, then the side spikes on the tread will not be where they should be for sure grip in the turn.

With wide tires on a narrow rim, the side studs will be too high and will not hold properly in the turn.

On narrow tires with a wide rim, the spikes will be from below and with a good slope, the bike will ride on the sidewall, and she is bald.

Below is the famous table compiled by Georg Boeder of tire and rim width recommendations

fractional inches) here.

Articles about tires:

  1. Which tire to choose for a bike
  2. What do the numbers and inscriptions on bicycle tires mean
  3. Is it possible to put different tires on different wheels of a bicycle and how to choose them?
  4. What is the compound and stiffness of bicycle tires
  5. What is TPI (EPI) for bicycle tires
  6. Bicycle Tire Wear: Causes and Treatment
  7. How to protect a bicycle wheel from punctures
  8. Bicycle tire pressure
  9. How to increase the grip of bicycle wheels with the road in winter on snow
  10. Lump (hernia) on a bicycle wheel. Why does it appear and can it be “treated”.

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Bicycle tire sizes

Every bicycle wears out a little as it is used. This also applies to bicycle tires, which are very important to change in a timely manner. To do this, you need to know the tire markings. It is necessary to be guided by the parameters set by the manufacturers. It should be borne in mind that the wheel, or rather its size, directly affects the parameters of a bicycle tire.

How to determine parameters

  • Before choosing the desired indicator, you should remember a few rules:
  • Wheels, 12", 14", 16", 18" and 20", designed for children's bikes and BMX;
  • 24" rim designed for teenage vehicle wheels;
  • 26" and 27.5" used for urban touring and mountain bikes;
  • Wheels in 29(28) inches can be found on road bikes and niners.


Most modern manufacturers use the European marking according to the ETRTO classification. This abbreviation stands for European Tire and Rim Technical Organization.

The following indicators apply here:

  • two-digit combination (37-622), in which the first value is the width of the tire in millimeters, the second is its diameter;
  • a combination of three numbers (28 x 15.8 x 13.8), indicating the approximate height and width of the bike tire, the size of the outer diameter.

By the way, Soviet-made bicycle tires had reverse double markings. The inner diameter of the tire was in first place, the width of the chamber was indicated in the second place.

To date, the marking adopted in Europe is considered the most accurate and convenient in comparison with the rest.

Dimensioning in inches

This application of indicators also consists of two numbers listed through a multiplication sign or a fraction. For example, if the values ​​are 28 x 1.4, then 28 equals the outer diameter of the tire, and 1.4 is its intended width in inches.


French marking may have the following meaning: 700 x 35C. Local manufacturers put down numerical values ​​for width, inner diameter and outer diameter. Therefore, in this case, the figure 700 is the approximate value of the outer diameter. In turn, the designation "C" determines the inner diameter. The indicator decreases with the movement of the letter to the beginning of the alphabet. Therefore, "A" is the smallest, and "D" is the largest. In the above example, the value "C" defines an internal diameter of 622 mm. This system of recording values ​​is not applicable to all bicycles (for example, not used for mountain bikes).

How to determine the bore diameter?

So, if you need a bicycle tire, you should initially select the diameter of the wheel rim.

Diameter size 28 and 29 equals 622 mm. These two tires differ only in height and thickness.
27.5-inch wheels require a bore diameter of 584 and 590 mm.

Learn more