How to find tire diameter

Tire Size Calculator

Tire Size Calculator Chart for 13" Wheels

21" Tire Diameter

185/60R13 = 21.7x7.3R13
215/50R13 = 21.5X8.5R13
225/45R13 = 21x8.9R13
225/50R13 = 21.9x8.9R13
255/40R13 = 21x10R13

22" Tire Diameter

155/80R13 = 22.8x6.1R13
175/70R13 = 22.6x6.9R13
205/60R13 = 22.7x8.1R13
22X8R13

23" Tire Diameter

165/80R13 = 23.4X6.5R13
185/70R13 = 23.2x7.3R13

24" Tire Diameter

175/80R13 = 24x6.9R13
185/80R13 = 24.7x7.3R13
24.5X8R13
24.5X9R13

Tire Size Calculator Chart for 14" Wheels

19" Tire Diameter

105/70R14 = 19.8X4.1R14

20" Tire Diameter

115/70R14 = 20.3X4.5R14
125/70R14 = 20.9X4.9R14

21" Tire Diameter

165/55R14 = 21.1X6.5R14

22" Tire Diameter

135/80R14 = 22.5X5.3R14
165/65R14 = 22.4x6.5R14
185/55R14 = 22x7.3R14
185/60R14 = 22.7x7.3R14
195/55R14 = 22. 4x7.7R14
205/50R14 = 22.1x8.1R14
205/55R14 = 22.9x8.1R14
225/50R14 = 22.9x8.9R14

23" Tire Diameter

175/65R14 = 23x6.9R14
175/70R14 = 23.6x6.9R14
185/65R14 = 23.5x7.3R14
195/60R14 = 23.2x7.7R14
205/60R14 = 23.7x8.1R14

24" Tire Diameter

185/70R14 = 24.2x7.3R14
185/75R14 = 24.9X7.3R14
195/65R14 = 24x7.7R14
195/70R14 = 24.7x7.7R14
215/60R14 = 24.2x8.5R14
225/60R14 = 24.6x8.9R14

25" Tire Diameter

185R14 = 25.7x7.3R14
195/75R14 = 25.5x7.7R14
205/70R14 = 25.3x8.1R14
215/70R14 = 25.9x8.5R14
235/60R14 = 25.1x9.3R14
245/60R14 = 25.6x9.6R14

26" Tire Diameter

195R14 = 26.2x7.8R14
205/75R14 = 26.1x8.1R14
215/75R14 = 26.7x8.5R14
225/70R14 = 26.4x8.9R14
26X8.5R14

27" Tire Diameter

205R14 = 27x8.2R14
27X8.5R14
27X9.5R14

28" Tire Diameter

28X10R14

30" Tire Diameter

30X10R14

Tire Size Calculator Chart for 15" Wheels

20" Tire Diameter

105/70R15 = 20.

8X4.1R15

21" Tire Diameter

115/70R15 = 21.3X4.5R15
125/70R15 = 21.9X4.9R15
165/50R15 = 21.5X6.5R15
195/45R15 = 21.9x7.7R15

22" Tire Diameter

125/80R15 = 22.9X4.9R15
145/65R15 = 22.4x5.7R15
155/60R15 = 22.3x6.1R15
165/60R15 = 22.8x6.5R15
175/55R15 = 22.6x6.9R15
195/50R15 = 22.7x7.7R15
22X8R15
22.5X4.5R15
245/40R15 = 22.7X9.6R15
275/35R15 = 22.6x10.8R15

23" Tire Diameter

135/80R15 = 23.5X5.3R15
165/65R15 = 23.4X6.5R15
175/60R15 = 23.3x6.9R15
185/55R15 = 23x7.3R15
185/60R15 = 23.7x7.3R15
195/55R15 = 23.4x7.7R15
205/50R15 = 23.1x8.1R15
205/55R15 = 23.9x8.1R15
225/45R15 = 23x8.9R15
225/50R15 = 23.9x8.9R15
295/35R15 = 23.1X11.6R15

24" Tire Diameter

135/90R15 = 24.6X5.3R15
155/80R15 = 24.8X6.1R15
175/65R15 = 24x6.9R15
185/65R15 = 24.5x7.3R15
195/60R15 = 24.2x7.7R15
205/60R15 = 24.7x8.1R15
225/55R15 = 24.7x8.

9R15
235/50R15 = 24.3x9.3R15
24X4.5R15
24X5R15
24.5X8R15
245/50R15 = 24.6x9.6R15
345/35R15 = 24.5x13.6R15

25" Tire Diameter

165/80R15 = 25.4X6.5R15
185/70R15 = 25.2x7.3R15
195/65R15 = 25x7.7R15
195/70R15 = 25.7x7.7R15
205/65R15 = 25.5x8.1R15
215/60R15 = 25.2x8.5R15
225/60R15 = 25.6x8.9R15
265/50R15 = 25.4X10.4R15
275/50R15 = 25.8x10.8R15

26" Tire Diameter

205/70R15 = 26.3x8.1R15
215/65R15 = 26x8.5R15
215/70R15 = 26.9x8.5R15
235/60R15 = 26.1x9.3R15
245/60R15 = 26.6x9.6R15
26X10R15
26X10.5R15
26X11.5R15
26X6R15
26X7.5R15
26X8R15
26X8.5R15
295/50R15 = 26.6x11.6R15

27" Tire Diameter

205/75R15 = 27.1x8.1R15
215/75R15 = 27.7x8.5R15
225/70R15 = 27.4x8.9R15
255/60R15 = 27x10R15
27X10.5R15
27X9.5R15
27.5X4.5R15
295/55R15 = 27.8X11.6R15
325/50R15 = 27.8x12.8R15
E78-15 = 27x6.5R15

28" Tire Diameter

225/75R15 = 28.

3x8.9R15
235/70R15 = 28x9.3R15
235/75R15 = 28.9x9.3R15
245/70R15 = 28.5X9.6R15
255/65R15 = 28.1x10R15
275/60R15 = 28x10.8R15
28X10.5R15
28X11.5R15
28X12.5R15
28X13.5R15
28X4.5R15
28X7.5R15
28X9R15

29" Tire Diameter

215/85R15 = 29.4X8.5R15
255/70R15 = 29.1x10R15
265/70R15 = 29.6x10.4R15
29X10.5R15
29X11.5R15
29X12.5R15
29X15.5R15
29X18R15
29X18.5R15
29X4.5R15
29X8.5R15
29.5X11.5R15
29.5X13.5R15
29.5X9R15
315/60R15 = 29.9x12.4R15
7R15 = 29.5x7.7R15

30" Tire Diameter

255/75R15 = 30.1x10R15
265/75R15 = 30.6x10.4R15
295/65R15 = 30.1x11.6R15
30X10R15
30X10.5R15
30X11.5R15
30X12.5R15
30X13.5R15
30X7R15
30X9R15
30X9.5R15

31" Tire Diameter

31X10.5R15
31X11R15
31X11.5R15
31X12.5R15
31X13R15
31X13.5R15
31X14.5R15
31X16.5R15
31X18R15
31X18.5R15
31X9.5R15

32" Tire Diameter

32X10.

5R15
32X11.5R15
32X14R15
32X16R15
32X17.5R15
32X18.5R15
32X9.5R15

33" Tire Diameter

33X10.5R15
33X11.5R15
33X12.5R15
33X13R15
33X13.5R15
33X14R15
33X14.5R15
33X15.5R15
33X16.5R15
33X19.5R15
33X21.5R15
33X9R15
33X9.5R15

34" Tire Diameter

34X10.5R15
34X12.5R15
34X9.5R15

35" Tire Diameter

35X10.5R15
35X12.5R15
35X13.5R15
35X14.5R15
35X15R15
35X15.5R15
35X16R15

36" Tire Diameter

36X12.5R15
36X13.5R15
36X14.5R15

37" Tire Diameter

37X12.5R15
37X13R15
37X13.5R15
37X14R15
37X14.5R15

38" Tire Diameter

38X12.5R15
38X13R15
38X14.5R15
38X15.5R15
38.5X11R15
38.5X13.5R15
38.5X14.5R15
38.5X15R15
38.5X16R15

39" Tire Diameter

39X13.5R15
39.5X13.5R15
39.5X15R15
39.5X18R15

40" Tire Diameter

40X16R15

42" Tire Diameter

42X14R15
42X15R15
42.

5X13.5R15

44" Tire Diameter

44X18.5R15
44X19.5R15
44X21R15

47" Tire Diameter

47X17R15

Tire Size Calculator Chart for 16" Wheels

22" Tire Diameter

125/70R16 = 22.9X4.9R16
175/50R16 = 22.9x6.9R16
195/40R16 = 22.1x7.7R16
195/45R16 = 22.9x7.7R16
205/40R16 = 22.5x8.1R16
215/35R16 = 21.9x8.5R16
215/40R16 = 22.8x8.5R16

23" Tire Diameter

125/80R16 = 23.9X4.9R16
135/70R16 = 23.4X5.3R16
175/55R16 = 23.6x6.9R16
185/50R16 = 23.3X7.3R16
195/50R16 = 23.7x7.7R16
205/45R16 = 23.3x8.1R16
215/45R16 = 23.6x8.5R16

24" Tire Diameter

125/85R16 = 24.4X4.9R16
125/90R16 = 24.9X4.9R16
135/80R16 = 24.5X5.3R16
175/60R16 = 24.3x6.9R16
185/55R16 = 24x7.3R16
185/60R16 = 24.7X7.3R16
195/55R16 = 24.4x7.7R16
205/50R16 = 24.1x8.1R16
205/55R16 = 24.9x8.1R16
215/50R16 = 24.5X8.5R16
225/45R16 = 24x8.9R16
225/50R16 = 24.

9x8.9R16
245/45R16 = 24.7x9.6R16

25" Tire Diameter

135/90R16 = 25.6X5.3R16
145/80R16 = 25.1X5.7R16
195/60R16 = 25.2x7.7R16
205/60R16 = 25.7x8.1R16
215/55R16 = 25.3x8.5R16
225/55R16 = 25.7x8.9R16
245/50R16 = 25.6x9.6R16
265/45R16 = 25.4X10.4R16
275/45R16 = 25.7x10.8R16
315/40R16 = 25.9X12.4R16

26" Tire Diameter

145/90R16 = 26.3X5.7R16
145/90R16 = 26.3X5.7R16
195/65R16 = 26X7.7R16
205/65R16 = 26.5x8.1R16
215/60R16 = 26.2x8.5R16
225/60R16 = 26.6x8.9R16
235/55R16 = 26.2x9.3R16
255/50R16 = 26x10R16
26X11.5R16

27" Tire Diameter

155/90R16 = 27X6.1R16
195/75R16 = 27.5x7.7R16
205/70R16 = 27.3x8.1R16
215/65R16 = 27x8.5R16
215/70R16 = 27.9x8.5R16
225/65R16 = 27.5x8.9R16
235/60R16 = 27.1x9.3R16
295/50R16 = 27.6x11.6R16
355/40R16 = 27.2X14R16

28" Tire Diameter

195/80R16 = 28.3x7.7R16
205/75R16 = 28.1X8.1R16
205/80R16 = 28.

9x8.1R16
215/75R16 = 28.7x8.5R16
225/70R16 = 28.4x8.9R16
235/65R16 = 28x9.3R16
255/60R16 = 28x10R16
28X11.5R16

29" Tire Diameter

225/75R16 = 29.3x8.9R16
235/70R16 = 29x9.3R16
235/75R16 = 29.9x9.3R16
245/70R16 = 29.5x9.6R16
255/65R16 = 29.1x10R16
275/60R16 = 29X10.8R16
285/60R16 = 29.5X11.2R16

30" Tire Diameter

215/85R16 = 30.4x8.5R16
235/80R16 = 30.8x9.3R16
245/75R16 = 30.5x9.6R16
255/70R16 = 30.1x10R16
265/70R16 = 30.6x10.4R16
285/65R16 = 30.6X11.2R16
30X11.5R16

31" Tire Diameter

225/85R16 = 31.1X8.9R16
235/85R16 = 31.7x9.3R16
265/75R16 = 31.6x10.4R16
275/70R16 = 31.2x10.8R16
285/70R16 = 31.7x11.2R16
31X10.5R16
31X11R16
31X11.5R16
31X12.5R16
7.5R16 = 31.8x8.7R16

32" Tire Diameter

265/80R16 = 32.7X10.4R16
285/75R16 = 32.8x11.2R16
305/70R16 = 32.8x12R16
32X10R16
32X11.5R16
32X9R16

33" Tire Diameter

255/85R16 = 33.

1x10R16
295/75R16 = 33.4x11.6R16
33X10.5R16
33X11.5R16
33X12.5R16
33X13R16
33X13.5R16
33X14R16
33X14.5R16
33X9.5R16
33.5X16.5R16

34" Tire Diameter

315/75R16 = 34.6x12.4R16
34X10.5R16
34X12.5R16
34X13.5R16
34X9R16
34.5X17R16

35" Tire Diameter

35X10.5R16
35X12.5R16
35X14.5R16
35X15R16
35X16R16
375/65R16 = 35.2x14.8R16

36" Tire Diameter

325/80R16 = 36.5x12.8R16
345/75R16 = 36.4x13.6R16
36X12.5R16
36X13R16
36X13.5R16
36X14.5R16

37" Tire Diameter

365/75R16 = 37.6x14.4R16
37X12.5R16
37X13R16
37X13.5R16
37X14R16
37X14.5R16
385/70R16 = 37.2x15.2R16
395/70R16 = 37.8x15.6R16

38" Tire Diameter

38X13R16
38X14.5R16
38X15.5R16
38.5X11R16
38.5X13.5R16
38.5X14.5R16
38.5X15R16

39" Tire Diameter

39X13.5R16
39.5X13.5R16
39.5X15R16

40" Tire Diameter

40X16R16

41" Tire Diameter

41X14.

5R16

42" Tire Diameter

42X14R16
42X15R16
42.5X13.5R16

44" Tire Diameter

44X19.5R16
44X21R16

46" Tire Diameter

46X19.5R16

Tire Size Calculator Chart for 16.5" Wheels

29" Tire Diameter

8.75R16.5 = 29.5x8.8R16.5

30" Tire Diameter

9.5R16.5 = 30.6x9.5R16.5

32" Tire Diameter

32X12R16.5

33" Tire Diameter

33X11.5R16.5
33X12.5R16.5
33X14R16.5
33X14.5R16.5
33X15.5R16.5

35" Tire Diameter

35X12.5R16.5
35X14.5R16.5
35X15R16.5
35X15.5R16.5
35X16R16.5
35X9.5R16.5

36" Tire Diameter

36X12.5R16.5
36X13.5R16.5
36X14.5R16.5
36X16R16.5

37" Tire Diameter

37X12.5R16.5
37X13R16.5
37X14R16.5

38" Tire Diameter

38X11R16.5
38X12.5R16.5
38X15.5R16.5
38.5X11R16.5
38.5X13.5R16.5
38.5X14.5R16.5
38.5X15R16.

5
38.5X16R16.5

39" Tire Diameter

39X13.5R16.5
39.5X13.5R16.5
39.5X15R16.5
39.5X18R16.5

42" Tire Diameter

42X14R16.5
42X15R16.5
42.5X13.5R16.5

43" Tire Diameter

43X14.5R16.5

44" Tire Diameter

44X18.5R16.5
44X18.5R16.5
44X19.5R16.5
44X21R16.5

47" Tire Diameter

47X17R16.5

48" Tire Diameter

48X12.5R16.5

49" Tire Diameter

49X21R16.5

Tire Size Calculator Chart for 17" Wheels

22" Tire Diameter

22X2.5R17

23" Tire Diameter

125/70R17 = 23.9X4.9R17
195/40R17 = 23.1x7.7R17
195/45R17 = 23.9x7.7R17
205/40R17 = 23.5x8.1R17
215/35R17 = 22.9x8.5R17
215/40R17 = 23.8x8.5R17
225/35R17 = 23.2x8.9R17
245/35R17 = 23.8x9.6R17

24" Tire Diameter

125/80R17 = 24.9X4.9R17
135/70R17 = 24.4X5.3R17
205/45R17 = 24.3x8.1R17
215/45R17 = 24.6x8.

5R17
225/40R17 = 24.1x8.9R17
235/40R17 = 24.4x9.3R17
245/40R17 = 24.7x9.6R17
275/35R17 = 24.6x10.8R17

25" Tire Diameter

115/95R17 = 25.6X4.5R17
135/80R17 = 25.5X5.3R17
145/70R17 = 25X5.7R17
155/70R17 = 25.5X6.1R17
205/50R17 = 25.1x8.1R17
205/55R17 = 25.9x8.1R17
215/50R17 = 25.5X8.5R17
225/45R17 = 25x8.9R17
225/50R17 = 25.9x8.9R17
235/45R17 = 25.3x9.3R17
245/45R17 = 25.7x9.6R17
255/40R17 = 25x10R17
265/40R17 = 25.3x10.4R17
275/40R17 = 25.7x10.8R17
295/35R17 = 25.1x11.6R17
315/35R17 = 25.7x12.4R17

26" Tire Diameter

135/90R17 = 26.6X5.3R17
145/80R17 = 26.1X5.7R17
155/80R17 = 26.8X6.1R17
215/55R17 = 26.3x8.5R17
225/55R17 = 26.7x8.9R17
235/50R17 = 26.3x9.3R17
245/50R17 = 26.6x9.6R17
255/45R17 = 26x10R17
26X11.5R17
285/40R17 = 26x11.2R17
295/40R17 = 26.3x11.6R17
335/35R17 = 26.2x13.2R17

27" Tire Diameter

145/90R17 = 27.

3X5.7R17
165/80R17 = 27.4X6.5R17
215/60R17 = 27.2x8.5R17
225/60R17 = 27.6x8.9R17
235/55R17 = 27.2x9.3R17
245/55R17 = 27.6x9.6R17
255/50R17 = 27x10R17
275/50R17 = 27.8X10.8R17
305/45R17 = 27.8X12R17
345/40R17 = 27.9x13.6R17

28" Tire Diameter

155/90R17 = 28X6.1R17
165/90R17 = 28.7X6.5R17
215/65R17 = 28x8.5R17
215/70R17 = 28.9x8.5R17
225/65R17 = 28.5x8.9R17
235/60R17 = 28.1x9.3R17
245/60R17 = 28.6X9.6R17
255/55R17 = 28x10R17
275/55R17 = 28.9x10.8R17

29" Tire Diameter

175/90R17 = 29.4X6.9R17
225/70R17 = 29.4x8.9R17
235/65R17 = 29x9.3R17
245/65R17 = 29.5x9.6R17
255/60R17 = 29x10R17
265/60R17 = 29.5x10.4R17

30" Tire Diameter

225/75R17 = 30.3x8.9R17
235/70R17 = 30x9.3R17
235/75R17 = 30.9x9.3R17
245/70R17 = 30.5x9.6R17
255/65R17 = 30.1x10R17
265/65R17 = 30.6x10.4R17
275/60R17 = 30x10.8R17
285/60R17 = 30.5X11.2R17

31" Tire Diameter

235/80R17 = 31.

8x9.3R17
245/75R17 = 31.5x9.6R17
255/70R17 = 31.1x10R17
265/70R17 = 31.6x10.4R17
275/65R17 = 31.1x10.8R17
285/65R17 = 31.6x11.2R17
31X10.5R17

32" Tire Diameter

235/85R17 = 32.7X9.3R17
255/75R17 = 32.1x10R17
275/70R17 = 32.2x10.8R17
285/70R17 = 32.7x11.2R17
305/65R17 = 32.6x12R17
32X10.5R17
32X11.5R17

33" Tire Diameter

255/80R17 = 33.1x10R17
285/75R17 = 33.8x11.2R17
295/70R17 = 33.3x11.6R17
305/70R17 = 33.8x12R17
33X10.5R17
33X12.5R17
33X13R17
33X13.5R17
33X9.5R17

34" Tire Diameter

275/80R17 = 34.3X10.8R17
315/70R17 = 34.4x12.4R17
325/70R17 = 34.9x12.8R17
34X10.5R17

35" Tire Diameter

35X10.5R17
35X11.5R17
35X12.5R17
35X13.5R17
35X14.5R17

36" Tire Diameter

355/70R17 = 36.6x14R17
36X12.5R17
36X13.5R17

37" Tire Diameter

37X12.5R17
37X13R17
37X13.5R17
37X14R17

38" Tire Diameter

38X13.

5R17
38X14.5R17
38X15.5R17
38.5X13.5R17
38.5X14.5R17

39" Tire Diameter

39X13.5R17
39.5X13.5R17
39.5X15R17

40" Tire Diameter

40X13.5R17
40X14.5R17
40X16R17

41" Tire Diameter

41X14.5R17

42" Tire Diameter

42X14R17
42X14.5R17
42X15R17
42.5X13.5R17

43" Tire Diameter

43X14.5R17

44" Tire Diameter

44X19.5R17
44X21R17

47" Tire Diameter

47X17R17

49" Tire Diameter

49X21R17

54" Tire Diameter

54X19.5R17

Tire Size Calculator Chart for 18" Wheels

23" Tire Diameter

215/35R18 = 23.9x8.5R18

24" Tire Diameter

125/70R18 = 24.9X4.9R18
205/40R18 = 24.5x8.1R18
215/40R18 = 24.8x8.5R18
225/35R18 = 24.2x8.9R18
235/35R18 = 24.5x9.3R18
245/35R18 = 24.8x9.6R18
285/30R18 = 24.7x11.2R18

25" Tire Diameter

135/70R18 = 25.

4X5.3R18
155/60R18 = 25.3X6.1R18
215/45R18 = 25.6x8.5R18
225/40R18 = 25.1x8.9R18
235/40R18 = 25.4x9.3R18
245/40R18 = 25.7x9.6R18
255/35R18 = 25x10R18
265/35R18 = 25.3x10.4R18
275/35R18 = 25.6x10.8R18
285/35R18 = 25.9x11.2R18
295/30R18 = 25x11.6R18
305/30R18 = 25.2x12R18
315/30R18 = 25.4x12.4R18
335/30R18 = 25.9x13.2R18

26" Tire Diameter

135/80R18 = 26.5X5.3R18
145/70R18 = 26X5.7R18
215/50R18 = 26.5X8.5R18
225/45R18 = 26x8.9R18
225/50R18 = 26.9x8.9R18
235/45R18 = 26.3x9.3R18
245/45R18 = 26.7x9.6R18
255/40R18 = 26x10R18
26X12R18
265/40R18 = 26.3x10.4R18
275/40R18 = 26.7x10.8R18
295/35R18 = 26.1x11.6R18
305/35R18 = 26.4x12R18
315/35R18 = 26.7x12.4R18
345/30R18 = 26.1x13.6R18

27" Tire Diameter

145/80R18 = 27.1X5.7R18
145/85R18 = 27.7X5.7R18
215/55R18 = 27.3x8.5R18
225/55R18 = 27.7x8.9R18
235/50R18 = 27.3x9.3R18
245/50R18 = 27.

6x9.6R18
255/45R18 = 27x10R18
265/45R18 = 27.4x10.4R18
275/45R18 = 27.7x10.8R18
285/40R18 = 27x11.2R18
295/40R18 = 27.3x11.6R18
305/40R18 = 27.6X12R18
315/40R18 = 27.9x12.4R18
325/35R18 = 27x12.8R18
345/35R18 = 27.5x13.6R18

28" Tire Diameter

155/85R18 = 28.4X6.1R18
225/60R18 = 28.6x8.9R18
235/55R18 = 28.2x9.3R18
245/55R18 = 28.6x9.6R18
255/50R18 = 28x10R18
265/50R18 = 28.4X10.4R18
285/45R18 = 28.1x11.2R18
295/45R18 = 28.5x11.6R18
305/45R18 = 28.8X12R18

29" Tire Diameter

155/90R18 = 29X6.1R18
165/90R18 = 29.7X6.5R18
225/65R18 = 29.5X8.9R18
235/60R18 = 29.1x9.3R18
245/60R18 = 29.6x9.6R18
255/55R18 = 29x10R18
265/55R18 = 29.5X10.4R18
275/55R18 = 29.9x10.8R18
285/50R18 = 29.2x11.2R18
325/45R18 = 29.5X12.8R18

30" Tire Diameter

175/90R18 = 30.4X6.9R18
235/65R18 = 30x9.3R18
245/65R18 = 30.5x9.6R18
255/60R18 = 30x10R18
265/60R18 = 30.

5x10.4R18
285/55R18 = 30.3x11.2R18

31" Tire Diameter

235/70R18 = 31X9.3R18
255/65R18 = 31.1x10R18
265/65R18 = 31.6x10.4R18
275/60R18 = 31x10.8R18
285/60R18 = 31.5x11.2R18

32" Tire Diameter

255/70R18 = 32.1x10R18
265/70R18 = 32.6x10.4R18
275/65R18 = 32.1x10.8R18
285/65R18 = 32.6x11.2R18
305/60R18 = 32.4x12R18

33" Tire Diameter

275/70R18 = 33.2x10.8R18
285/70R18 = 33.7x11.2R18
295/65R18 = 33.1x11.6R18
305/65R18 = 33.6x12R18
325/60R18 = 33.4x12.8R18
33X10.5R18
33X11.5R18
33X12.5R18
33X13R18
33X13.5R18

34" Tire Diameter

285/75R18 = 34.8x11.2R18
295/70R18 = 34.3X11.6R18
305/70R18 = 34.8x12R18
325/65R18 = 34.6x12.8R18
34X12.5R18

35" Tire Diameter

315/70R18 = 35.4x12.4R18
35X11.5R18
35X12.5R18
35X13R18
35X13.5R18
35X14.5R18

36" Tire Diameter

355/65R18 = 36.2x14R18
36X13.

5R18

37" Tire Diameter

37X11.5R18
37X12.5R18
37X13.5R18

38" Tire Diameter

38X13.5R18
38X14.5R18
38X15R18
38X15.5R18
38.5X14.5R18

40" Tire Diameter

40X13.5R18
40X14.5R18

41" Tire Diameter

41X14.5R18

Tire Size Calculator Chart for 19" Wheels

24" Tire Diameter

215/35R19 = 24.9x8.5R19
235/30R19 = 24.6x9.3R19
245/30R19 = 24.8x9.6R19
295/25R19 = 24.8X11.6R19

25" Tire Diameter

115/70R19 = 25.3X4.5R19
125/70R19 = 25.9X4.9R19
225/35R19 = 25.2x8.9R19
235/35R19 = 25.5x9.3R19
245/35R19 = 25.8x9.6R19
255/30R19 = 25x10R19
265/30R19 = 25.3x10.4R19
275/30R19 = 25.5x10.8R19
285/30R19 = 25.7x11.2R19
315/25R19 = 25.2x12.4R19

26" Tire Diameter

135/70R19 = 26.4X5.3R19
225/40R19 = 26.1x8.9R19
235/40R19 = 26.4x9.3R19
245/40R19 = 26.7x9.6R19
255/35R19 = 26x10R19
265/35R19 = 26.

3x10.4R19
275/35R19 = 26.6x10.8R19
285/35R19 = 26.9x11.2R19
295/30R19 = 26x11.6R19
305/30R19 = 26.2x12R19
315/30R19 = 26.4x12.4R19
325/30R19 = 26.7x12.8R19
335/30R19 = 26.9x13.2R19

27" Tire Diameter

155/70R19 = 27.5x6.1R19
175/60R19 = 27.3x6.9R19
225/45R19 = 27x8.9R19
235/45R19 = 27.3x9.3R19
245/45R19 = 27.7x9.6R19
255/40R19 = 27x10R19
265/40R19 = 27.3x10.4R19
275/40R19 = 27.7x10.8R19
295/35R19 = 27.1x11.6R19
305/35R19 = 27.4X12R19
315/35R19 = 27.7x12.4R19
345/30R19 = 27.1x13.6R19
355/30R19 = 27.4x14R19

28" Tire Diameter

145/80R19 = 28.1X5.7R19
155/80R19 = 28.8X6.1R19
225/55R19 = 28.7x8.9R19
235/50R19 = 28.3x9.3R19
245/50R19 = 28.6x9.6R19
255/45R19 = 28x10R19
265/45R19 = 28.4X10.4R19
275/45R19 = 28.7x10.8R19
285/40R19 = 28x11.2R19
295/40R19 = 28.3X11.6R19
315/40R19 = 28.9x12.4R19
345/35R19 = 28.5x13.6R19

29" Tire Diameter

235/55R19 = 29.

2x9.3R19
245/55R19 = 29.6x9.6R19
255/50R19 = 29x10R19
265/50R19 = 29.4x10.4R19
275/50R19 = 29.8X10.8R19
285/45R19 = 29.1x11.2R19
295/45R19 = 29.5x11.6R19

30" Tire Diameter

165/90R19 = 30.7X6.5R19
175/80R19 = 30X6.9R19
255/55R19 = 30x10R19
265/55R19 = 30.5x10.4R19
275/55R19 = 30.9x10.8R19

31" Tire Diameter

235/65R19 = 31X9.3R19
255/60R19 = 31x10R19

Tire Size Calculator Chart for 20" Wheels

25" Tire Diameter

215/30R20 = 25.1X8.5R20
225/30R20 = 25.3x8.9R20
235/30R20 = 25.6x9.3R20
245/30R20 = 25.8x9.6R20
275/25R20 = 25.4X10.8R20
285/25R20 = 25.6x11.2R20
295/25R20 = 25.8x11.6R20

26" Tire Diameter

145/60R20 = 26.9X5.7R20
225/35R20 = 26.2x8.9R20
235/35R20 = 26.5x9.3R20
245/35R20 = 26.8x9.6R20
255/30R20 = 26x10R20
265/30R20 = 26.3x10.4R20
275/30R20 = 26.5x10.8R20
285/30R20 = 26.7x11.2R20
305/25R20 = 26x12R20
315/25R20 = 26.

2x12.4R20
325/25R20 = 26.4x12.8R20
335/25R20 = 26.6x13.2R20
345/25R20 = 26.8X13.6R20

27" Tire Diameter

155/60R20 = 27.3x6.1R20
155/65R20 = 27.9X6.1R20
165/60R20 = 27.8X6.5R20
175/55R20 = 27.6x6.9R20
195/50R20 = 27.7x7.7R20
215/45R20 = 27.6x8.5R20
225/40R20 = 27.1X8.9R20
235/40R20 = 27.4x9.3R20
245/40R20 = 27.7x9.6R20
255/35R20 = 27x10R20
265/35R20 = 27.3x10.4R20
275/35R20 = 27.6x10.8R20
285/35R20 = 27.9x11.2R20
295/30R20 = 27x11.6R20
305/30R20 = 27.2x12R20
315/30R20 = 27.4x12.4R20
325/30R20 = 27.7x12.8R20
335/30R20 = 27.9x13.2R20

28" Tire Diameter

225/45R20 = 28X8.9R20
235/45R20 = 28.3x9.3R20
245/45R20 = 28.7x9.6R20
255/40R20 = 28x10R20
265/40R20 = 28.3x10.4R20
275/40R20 = 28.7x10.8R20
295/35R20 = 28.1x11.6R20
305/35R20 = 28.4x12R20
315/35R20 = 28.7x12.4R20
345/30R20 = 28.1x13.6R20

29" Tire Diameter

235/50R20 = 29.

3X9.3R20
245/50R20 = 29.6x9.6R20
255/45R20 = 29x10R20
265/45R20 = 29.4x10.4R20
275/45R20 = 29.7x10.8R20
285/40R20 = 29x11.2R20
295/40R20 = 29.3x11.6R20
305/40R20 = 29.6X12R20
325/35R20 = 29X12.8R20

30" Tire Diameter

235/55R20 = 30.2x9.3R20
255/50R20 = 30x10R20
265/50R20 = 30.4x10.4R20
275/50R20 = 30.8x10.8R20
285/45R20 = 30.1X11.2R20
295/45R20 = 30.5x11.6R20
305/45R20 = 30.8x12R20

31" Tire Diameter

245/60R20 = 31.6x9.6R20
255/55R20 = 31x10R20
275/55R20 = 31.9x10.8R20
285/50R20 = 31.2x11.2R20
295/50R20 = 31.6x11.6R20
31X18R20

32" Tire Diameter

265/60R20 = 32.5x10.4R20
285/55R20 = 32.3x11.2R20
295/55R20 = 32.8X11.6R20
305/50R20 = 32x12R20
315/50R20 = 32.4x12.4R20
325/50R20 = 32.8x12.8R20

33" Tire Diameter

275/60R20 = 33x10.8R20
285/60R20 = 33.5x11.2R20
295/60R20 = 33.9X11.6R20
305/55R20 = 33.2x12R20
33X11.

5R20
33X12R20
33X12.5R20
33X13.5R20

34" Tire Diameter

275/65R20 = 34.1x10.8R20
285/65R20 = 34.6x11.2R20
305/60R20 = 34.4x12R20
315/60R20 = 34.9x12.4R20
355/50R20 = 34X14R20

35" Tire Diameter

295/65R20 = 35.1X11.6R20
325/60R20 = 35.4x12.8R20
35X11.5R20
35X12.5R20
35X13R20
35X13.5R20
35X14.5R20

36" Tire Diameter

355/60R20 = 36.8x14R20
36X13.5R20
36X15.5R20

37" Tire Diameter

37X11.5R20
37X12.5R20
37X13.5R20
37X14.5R20

38" Tire Diameter

38X13.5R20
38X14.5R20
38X15.5R20
38.5X13.5R20
38.5X14.5R20

39" Tire Diameter

39X13.5R20
39.5X13.5R20
39.5X15R20

40" Tire Diameter

40X13.5R20
40X14.5R20
40X15.5R20

41" Tire Diameter

41X14.5R20

42" Tire Diameter

42X14.5R20
42X15R20
42.5X13.5R20

43" Tire Diameter

43X14.

5R20

44" Tire Diameter

44X19.5R20
44X19.5R20
44X21R20

45" Tire Diameter

45X14.5R20

46" Tire Diameter

46X19.5R20

49" Tire Diameter

49X21R20

54" Tire Diameter

54X19.5R20

Tire Size Calculator Chart for 21" Wheels

26" Tire Diameter

245/30R21 = 26.8x9.6R21
295/25R21 = 26.8x11.6R21

27" Tire Diameter

245/35R21 = 27.8x9.6R21
255/30R21 = 27x10R21
265/30R21 = 27.3x10.4R21
275/30R21 = 27.5x10.8R21
285/30R21 = 27.7x11.2R21
305/25R21 = 27x12R21
325/25R21 = 27.4x12.8R21

28" Tire Diameter

245/40R21 = 28.7x9.6R21
255/35R21 = 28X10R21
265/35R21 = 28.3x10.4R21
275/35R21 = 28.6x10.8R21
285/35R21 = 28.9x11.2R21
295/30R21 = 28x11.6R21
305/30R21 = 28.2x12R21
315/30R21 = 28.4X12.4R21
325/30R21 = 28.7x12.8R21
355/25R21 = 28x14R21

29" Tire Diameter

245/45R21 = 29.

7X9.6R21
255/40R21 = 29X10R21
265/40R21 = 29.3x10.4R21
275/40R21 = 29.7x10.8R21
295/35R21 = 29.1x11.6R21
305/35R21 = 29.4X12R21
315/35R21 = 29.7X12.4R21

30" Tire Diameter

265/45R21 = 30.4x10.4R21
275/45R21 = 30.7x10.8R21
285/40R21 = 30X11.2R21
295/40R21 = 30.3x11.6R21
315/40R21 = 30.9X12.4R21

31" Tire Diameter

255/50R21 = 31x10R21
275/50R21 = 31.8X10.8R21
285/45R21 = 31.1x11.2R21
325/40R21 = 31.2X12.8R21

Tire Size Calculator Chart for 22" Wheels

27" Tire Diameter

235/30R22 = 27.6x9.3R22
245/30R22 = 27.8x9.6R22
275/25R22 = 27.4x10.8R22
285/25R22 = 27.6x11.2R22
295/25R22 = 27.8x11.6R22

28" Tire Diameter

255/30R22 = 28x10R22
265/30R22 = 28.3x10.4R22
275/30R22 = 28.5X10.8R22
285/30R22 = 28.7x11.2R22
305/25R22 = 28x12R22
315/25R22 = 28.2x12.4R22
335/25R22 = 28.6x13.2R22

29" Tire Diameter

255/35R22 = 29x10R22
265/35R22 = 29.

3x10.4R22
275/35R22 = 29.6X10.8R22
285/35R22 = 29.9x11.2R22
295/30R22 = 29x11.6R22
305/30R22 = 29.2x12R22
315/30R22 = 29.4X12.4R22

30" Tire Diameter

255/40R22 = 30X10R22
265/40R22 = 30.3x10.4R22
275/40R22 = 30.7x10.8R22
295/35R22 = 30.1X11.6R22
305/35R22 = 30.4X12R22
315/35R22 = 30.7X12.4R22

31" Tire Diameter

255/45R22 = 31X10R22
265/45R22 = 31.4X10.4R22
275/45R22 = 31.7x10.8R22
285/40R22 = 31x11.2R22
295/40R22 = 31.3x11.6R22
305/40R22 = 31.6x12R22
325/35R22 = 31X12.8R22

32" Tire Diameter

275/50R22 = 32.8x10.8R22
285/45R22 = 32.1x11.2R22
305/45R22 = 32.8x12R22

33" Tire Diameter

285/50R22 = 33.2x11.2R22
33X12.5R22
33X14.5R22
355/40R22 = 33.2X14R22

34" Tire Diameter

285/55R22 = 34.3X11.2R22
295/55R22 = 34.8X11.6R22
305/50R22 = 34x12R22
325/50R22 = 34.8x12.8R22

35" Tire Diameter

35X12.

5R22
35X14.5R22
35X15.5R22
375/45R22 = 35.3X14.8R22

36" Tire Diameter

325/55R22 = 36.1x12.8R22
335/55R22 = 36.5X13.2R22

37" Tire Diameter

325/60R22 = 37.4x12.8R22
37X12.5R22
37X13.5R22

38" Tire Diameter

355/60R22 = 38.8x14R22
38X13.5R22
38X15.5R22

40" Tire Diameter

40X14.5R22
40X15.5R22

41" Tire Diameter

41X14.5R22

42" Tire Diameter

42.5X13.5R22

Tire Size Calculator Chart for 23" Wheels

28" Tire Diameter

265/25R23 = 28.2X10.4R23

30" Tire Diameter

285/35R23 = 30.9x11.2R23
325/30R23 = 30.7X12.8R23

31" Tire Diameter

275/40R23 = 31.7X10.8R23

32" Tire Diameter

285/40R23 = 32x11.2R23
305/40R23 = 32.6x12R23
325/35R23 = 32X12.8R23

Tire Size Calculator Chart for 24" Wheels

29" Tire Diameter

275/25R24 = 29.4x10.8R24

30" Tire Diameter

255/30R24 = 30x10R24
275/30R24 = 30.

5x10.8R24
285/30R24 = 30.7x11.2R24

31" Tire Diameter

285/35R24 = 31.9x11.2R24
295/30R24 = 31X11.6R24

32" Tire Diameter

295/35R24 = 32.1x11.6R24
305/35R24 = 32.4x12R24
315/35R24 = 32.7x12.4R24
405/25R24 = 32x15.9R24

33" Tire Diameter

285/40R24 = 33x11.2R24
295/40R24 = 33.3x11.6R24

34" Tire Diameter

385/35R24 = 34.6x15.2R24

35" Tire Diameter

325/45R24 = 35.5x12.8R24
35X12.5R24
35X13.5R24
375/40R24 = 35.8X14.8R24

36" Tire Diameter

315/50R24 = 36.4X12.4R24

37" Tire Diameter

37X13.5R24
37X14.5R24

38" Tire Diameter

38X13.5R24
38X14R24
38X15.5R24

40" Tire Diameter

40X13.5R24
40X14.5R24
40X15.5R24

42" Tire Diameter

42X15.5R24

Tire Size Calculator Chart for 26" Wheels

31" Tire Diameter

275/25R26 = 31.4x10.8R26
295/25R26 = 31.

8x11.6R26

33" Tire Diameter

295/30R26 = 33x11.6R26
305/30R26 = 33.2x12R26

35" Tire Diameter

315/40R26 = 35.9x12.4R26

37" Tire Diameter

37X13.5R26

38" Tire Diameter

38X15.5R26

40" Tire Diameter

40X13.5R26
40X15.5R26

42" Tire Diameter

42X15.5R26

Tire Size Calculator Chart for 28" Wheels

33" Tire Diameter

295/25R28 = 33.8x11.6R28

37" Tire Diameter

325/35R28 = 37x12.8R28

40" Tire Diameter

40X15.5R28

42" Tire Diameter

42X15.5R28

Tire Size Calculator Chart for 30" Wheels

37" Tire Diameter

315/30R30 = 37.4x12.4R30

Tire Size Calculator | Tire Size Comparison

Created by Steven Wooding

Reviewed by Dominik Czernia, PhD and Jack Bowater

Last updated: Nov 05, 2022

Table of contents:

How do tire sizes work?
How to calculate tire size?
How to use the tire size calculator?
Example of tire size comparison

Using our tire size calculator, you can find the tire measurements of your car tire, such as its diameter, sidewall height, and circumference. It's also a tire size comparison calculator, allowing you to compare your current tire with the one you are thinking of buying. It tells you whether the new tire will be a good fit, and how it might affect your speed dial.

The text below also explains:

How tire sizes work;
What the tire code you see on your tire means; and
How to use our tire size calculator to compare tires.

So let the tremendous tire comparison begin!

How do tire sizes work?

You've probably seen this strange set of numbers and letters on your car's tires and wondered what they mean. It's called a tire code, and it specifies the size and type of tire. Getting properly sized parts for your vehicle is crucial, so make sure to visit the wheel offset calculator to get that right, too.
Let's go through each part of the code and make you a tire code expert.

By F l a n k e r – Own work, CC BY 3.

0, wikimedia.org. Modified version, focusing on the tire size code.

The first letter is optional, so you might not always see it. It gives information about the intended use or the class of vehicle the tire fits. Possible values are:

P: Passenger car
LT: Light Truck
ST: Special Trailer
T: Temporary (e.g., "space-saver" spare wheels)

Up next is a 3-digit number that indicates the width of the tire in millimeters, measured at the widest point of the sidewall (technically called the "nominal section width"). Expect the width of the tire actually in contact with the road to be smaller than this value.

Next is a forward-slash for character separation, then there's a 2- or 3-digit number representing the profile of the tire. This number is the ratio of sidewall height to the tire's width as a percentage (also called the aspect ratio). So, for example, if the value was 50%, the sidewall height would be half of the width. If it is not present, you can assume a profile ratio of 82%. If the number is more than 200, then it represents the tire's diameter in millimeters.

Following the profile ratio, you may see an optional letter indicating the type of tire construction. Radial (R) is now the most common and the standard design for car tires today, with over a 98% market share. Here is a summary of radial and some other constructions you may see:

R: radial – cords that make up the structure of the tire are at right angles to the direction of travel;
D: diagonal (or cross-ply) – cords are at an angle diagonal to the direction of travel;
B: bias belt – same as diagonal, but with an extra layer of reinforcing belts under the tread; and
If no letter is present, a diagonal tire construction is assumed

The wheel diameter is indicated by the final 1- or 2- digit number, in inches. You might also see the wheel (or rim) diameter given to an accuracy of half an inch. In some rare cases, the number is three digits long. In that case, it represents the wheel diameter in millimeters.

So that's the tire code and tire size explained.

If you found this calculator useful our fuel cost calculator may also be of interest to you.

How to calculate tire size?

Let's learn how to find tire sizes. We've got the tire code and the data required for us to calculate various tire measurements, such as the tire diameter and sidewall height.

To calculate the sidewall height, we multiply the profile ratio by the tire width (dividing by 100 as the ratio is a percentage). The formula is, therefore:

sidewall height = profile ratio × width / 100

So, for the tire code shown in the figure above, P215/65R15, you would calculate the sidewall height as:

sidewall height = 65 × 215 / 100 = 139. 75 mm

Converting to inches (divide by 2.54 × 10), that's 5.5 inches. We know the diameter of the wheel is 15 inches, so the diameter of the tire is given by:

tire diameter = wheel diameter + (2 × sidewall height)

So, for our example, that's:

tire diameter = 15 + (2 × 5.5) = 26 inches

To calculate the circumference, we use the classic circle equation:

circumference = π × diameter

So, for our exemplary tire, the tire circumference is:

circumference = 3.1416 × 26 = 81.7 inches

Our tire size calculator can also tell you how many revolutions a tire completes in a mile (or kilometer). This value is found by converting a mile into inches and dividing the result by the tire's circumference:

revolutions number = 63360 / 81.7 = 775

How to use the tire size calculator?

Using our tire size calculator is easy:

Enter the values for the tire's width, profile ratio, and wheel size diameter obtained from either the tire code or from measuring into the first three fields of the calculator. You may also specify the construction type of the tire, though it will not affect any tire's size dimensions.
You will then see confirmation of the tire code.
As a result, you will see the tire diameter, sidewall height, circumference, and the number of revolutions completed per mile.
Don't forget to click on the units to switch to your preferred unit for each input and output.

Want to compare one tire with another one? Then select "Yes" when asked, "Compare with another tire?". The same inputs and outputs will appear for the second tire.

At the end of the tire size conversion calculator, you will see the absolute difference in the diameters of the two tires and the corresponding percentage change. Note that if you are looking to put this second tire on your vehicle, the difference in tire diameter should be no more than 2. 5% smaller or larger. If it is larger, the tire might foul the wheel arch of your car, or the tire may be too weighty for the car's suspension and shock absorbers. Too small a tire size may mean the vehicle's ground clearance is not practical (scrapping speed bumps) anymore.

Changing the tire diameter will also affect the speedometer reading when compared to the actual speed of the car. Fortunately, this is also a tire size speedometer calculator too! Enter a speed into the "Speedometer reading" row, and you see the actual speed displayed. This information could be important when keeping to speed limits. If it is a modern vehicle, you might be able to set the tire diameter size in the car's electronics system. Your garage should be able to help you out, depending on the make and model of your vehicle.

✅ Now that you know your tire size, you can use it in the speedometer gear calculator to find the right gear for your vehicle, too!

Example of tire size comparison

Let's take a more in-depth look at the tire comparison feature by comparing two tires with the tire codes 195/65R15 and 195/85R15. If you enter these values into the tire size calculator, we can check them out in more detail.

The diameter calculated for the first tire is 25 inches, and the second one is just over 28 inches in diameter. That's a difference of over 3 inches. You'll see that's a 12.3% difference - well over the recommended amount. The percentage change is calculated like this:

percentage change = 100 × absolute difference / first tire diameter

So, for this example, inputting the values gives:

percentage change = 100 × 3.07 / 25 = 12.3 %

This percentage change in tire diameter is also the difference between the speedometer reading and the actual speed of the car. For example, if the speedometer says 30 mph, the actual speed will be:

actual speed = 30 × (1 + (12.3 / 100)) = 33.69 mph

Steven Wooding

Profile ratio

Wheel diameter

Tire construction

Tire Code
???/??R??

Tire diameter

Sidewall height

Circumference

Revolutions

Tire comparison

Compare with another tire?

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How to determine the diameter of the wheel

Author: Sochi Auto Remont

Heading: Tips for a car enthusiast

First of all, we find the exact size of the wheel diameter, and then we go to buy the appropriate tires. How correctly you do this, how correctly and steadily your car will behave on the road. The diameter of the wheel is a composite value, which is why care is required in the calculations. How to determine the diameter of the wheel is our topic today.

Determining the diameter and choosing the right tires!

How to determine the diameter of a wheel

Step-by-step instructions on how to determine the diameter of a wheel

How to determine the diameter of a wheel

Step 1. The simplest formula is used for calculations: it is necessary to add the sum of two tire profile heights to the diameter of the wheel. This method is applicable only when calculating for passenger cars.

Step 2. Take a tape measure for the usual way of measuring the diameter of the wheel. Each parameter taken from the formula must be measured separately. The values that you get must be converted to inches (since the unit of measurement for the diameter of a car wheel is an inch). We translate into inches as follows: divide each number obtained by 2.54. Then you need to add together the values obtained as a result of the measurement. The resulting number is the diameter of your wheel.

Step 3. You don't have to do mathematical calculations, just apply an even simpler calculation formula. How to determine the diameter of the wheel using the second formula - you need to take the number that indicates the width of the rim, and add 20% to it, so you get the full width of your wheel. If the tire width is narrow, then the difference between the total width of the wheels and the width of the rim will be 15%.

Step 4. Experts do not recommend making the wheel diameter larger than the allowable limits. The permissible norm is to increase the diameter of the wheel by a maximum of several centimeters. A wheel size that exceeds the allowable values will have a bad effect on the chassis of the car, as well as touch the wheel arches. It will be necessary to change the alignment of the car, which will then affect fuel consumption.

Step 5. When maximizing the diameter of the rim, choose an appropriately low profile tire compared to the standard tyre. Do not forget that low-profile tires do not have the same margin of safety as a standard tire. It is necessary to maintain a balance between the overall diameter of the wheel and disk. Plus, low-profile tires, along with the maximum diameter of the disk, deprives you of the usual comfort, and also affects the chassis.

Step 6. Wheel rim diameter is an important part of a car wheel. You need to know and remember that wheel parameters in terms of rim diameter can range from 10 to 23 inches. The parameters of small indicators refer to motorcycles and mopeds. Large indicators are used among powerful vehicles.

Useful tips for car owners.

If you have doubts about your calculations, you can always turn to specialists. How to determine the diameter of the wheel - experienced specialists at a glance can give you accurate information on your wheels. To do this, you can drive to any auto service or car service station. There you will receive the exact information you are interested in.

We told you how to determine the diameter of the wheel, try it!

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How to choose and measure the wheel diameter

Valery Leonidov

31 August 2017 11:21

A large number of manufacturers, shapes, sizes, patterns and other indicators of car tires are shocking for an inexperienced car owner. The right choice is the key not only to a long service life of the wheels, but also to safety while driving, since the appropriately selected rubber tread is responsible for the car's grip on the road. For the right choice, you need to take into account some subtleties, determine the priority characteristics that rubber should have.

Today there are a lot of options to get the necessary information. For example, you can consult online, on the site, but in any case you should know what to ask. If you are changing tires or rims from smaller to larger and vice versa, you need to know a thing or two about sizing and other intricacies of selection. As a rule, cars are produced with factory wheels, which are somewhat smaller than we might like. Such a replacement carries more aesthetic meaning, but it still has practicality.

Larger wheels up to 18 inches have a positive effect on cornering, traction, braking performance, ride comfort and steering feel, while negatively affecting acceleration and fuel economy due to the greater weight of the wheels themselves. In 19 inches and up, tests have shown that the positive improvements have disappeared, and acceleration and fuel economy have deteriorated. So the large diameter of the wheels and tires, apart from beauty, does not carry anything in itself. Car owners usually set a smaller radius if they have a second set of tires, such as winter tires that they install every winter. Winter tires tend to get a lot more expensive at sizes over 17 inches. In addition, the wider the tire, the more effective it is on snow and ice.

So if you have 18" or 19" wheels and want an extra set of wheels for winter tires, it's a good idea to go down to 17" or 16" wheels. These diameters are not only cheaper, easier to find, but also have better grip than other sizes.

Speedometer, odometer, traction control, torque and gear settings are based on the distance your tire travels in one full revolution, which is determined by the outside diameter of the tire and wheel combined. A tire with a different outer diameter will travel a different distance compared to one revolution with different torque. When changing the diameter of your rims, you must make sure that the new wheels in the assembly have the same overall diameter as the old one or your speedometer, otherwise the readings of these gauges will not be correct.

How to read the numbers on tires

Tires have 3 digits, eg 225/55/16. For a tire of this size, the first number (225) indicates the width of the tire in millimeters.