Bike gear calculator

A gear chart shows every chainring and cassette combination on one page. Enter the smallest and largest sprockets you own to see the ratios, the distance each turn covers and the resulting speed at a steady cadence.

Smallest chainring teeth

Largest chainring teeth

Smallest rear cog teeth

Largest rear cog teeth

Wheel diameter with tyre

A 700c rim with a 25 mm tyre is about 672 mm across.

Reference cadence

Gear range (largest to smallest ratio): 3.74
Speed in the largest gear at the reference cadence: 51.8
Speed in the smallest gear at the reference cadence: 13.8

Estimates for information only. Not financial, medical, legal or engineering advice. See the Terms.

Gear chart
Chainring	Cog	Gear ratio	Gear inches	Development (m)	Speed (km/h)
34.00	11.00	3.09	81.78	6.53	35.24
34.00	12.00	2.83	74.96	5.98	32.30
34.00	13.00	2.62	69.19	5.52	29.82
34.00	14.00	2.43	64.25	5.13	27.69
34.00	15.00	2.27	59.97	4.79	25.84
34.00	16.00	2.13	56.22	4.49	24.23
34.00	17.00	2.00	52.91	4.22	22.80
34.00	18.00	1.89	49.97	3.99	21.53
34.00	19.00	1.79	47.34	3.78	20.40
34.00	20.00	1.70	44.98	3.59	19.38
34.00	21.00	1.62	42.83	3.42	18.46
34.00	22.00	1.55	40.89	3.26	17.62
34.00	23.00	1.48	39.11	3.12	16.85
34.00	24.00	1.42	37.48	2.99	16.15
34.00	25.00	1.36	35.98	2.87	15.50
34.00	26.00	1.31	34.60	2.76	14.91
34.00	27.00	1.26	33.32	2.66	14.36
34.00	28.00	1.21	32.13	2.56	13.84
35.00	11.00	3.18	84.18	6.72	36.27
35.00	12.00	2.92	77.17	6.16	33.25
35.00	13.00	2.69	71.23	5.68	30.69
35.00	14.00	2.50	66.14	5.28	28.50
35.00	15.00	2.33	61.73	4.93	26.60
35.00	16.00	2.19	57.87	4.62	24.94
35.00	17.00	2.06	54.47	4.35	23.47
35.00	18.00	1.94	51.44	4.11	22.17
35.00	19.00	1.84	48.74	3.89	21.00
35.00	20.00	1.75	46.30	3.69	19.95
35.00	21.00	1.67	44.09	3.52	19.00
35.00	22.00	1.59	42.09	3.36	18.14
35.00	23.00	1.52	40.26	3.21	17.35
35.00	24.00	1.46	38.58	3.08	16.63
35.00	25.00	1.40	37.04	2.96	15.96
35.00	26.00	1.35	35.61	2.84	15.35
35.00	27.00	1.30	34.30	2.74	14.78
35.00	28.00	1.25	33.07	2.64	14.25
36.00	11.00	3.27	86.59	6.91	37.31
36.00	12.00	3.00	79.37	6.33	34.20
36.00	13.00	2.77	73.26	5.85	31.57
36.00	14.00	2.57	68.03	5.43	29.31
36.00	15.00	2.40	63.50	5.07	27.36
36.00	16.00	2.25	59.53	4.75	25.65
36.00	17.00	2.12	56.03	4.47	24.14
36.00	18.00	2.00	52.91	4.22	22.80
36.00	19.00	1.89	50.13	4.00	21.60
36.00	20.00	1.80	47.62	3.80	20.52
36.00	21.00	1.71	45.35	3.62	19.54
36.00	22.00	1.64	43.29	3.45	18.65
36.00	23.00	1.57	41.41	3.30	17.84
36.00	24.00	1.50	39.69	3.17	17.10
36.00	25.00	1.44	38.10	3.04	16.42
36.00	26.00	1.38	36.63	2.92	15.78
36.00	27.00	1.33	35.28	2.81	15.20
36.00	28.00	1.29	34.02	2.71	14.66
37.00	11.00	3.36	88.99	7.10	38.35
37.00	12.00	3.08	81.57	6.51	35.15
37.00	13.00	2.85	75.30	6.01	32.45
37.00	14.00	2.64	69.92	5.58	30.13
37.00	15.00	2.47	65.26	5.21	28.12
37.00	16.00	2.31	61.18	4.88	26.36
37.00	17.00	2.18	57.58	4.59	24.81
37.00	18.00	2.06	54.38	4.34	23.43
37.00	19.00	1.95	51.52	4.11	22.20
37.00	20.00	1.85	48.94	3.91	21.09
37.00	21.00	1.76	46.61	3.72	20.09
37.00	22.00	1.68	44.50	3.55	19.17
37.00	23.00	1.61	42.56	3.40	18.34
37.00	24.00	1.54	40.79	3.25	17.58
37.00	25.00	1.48	39.16	3.12	16.87
37.00	26.00	1.42	37.65	3.00	16.22
37.00	27.00	1.37	36.26	2.89	15.62
37.00	28.00	1.32	34.96	2.79	15.06
38.00	11.00	3.45	91.40	7.29	39.38
38.00	12.00	3.17	83.78	6.69	36.10
38.00	13.00	2.92	77.33	6.17	33.32
38.00	14.00	2.71	71.81	5.73	30.94
38.00	15.00	2.53	67.02	5.35	28.88
38.00	16.00	2.38	62.83	5.01	27.08
38.00	17.00	2.24	59.14	4.72	25.48
38.00	18.00	2.11	55.85	4.46	24.07
38.00	19.00	2.00	52.91	4.22	22.80
38.00	20.00	1.90	50.27	4.01	21.66
38.00	21.00	1.81	47.87	3.82	20.63
38.00	22.00	1.73	45.70	3.65	19.69
38.00	23.00	1.65	43.71	3.49	18.84
38.00	24.00	1.58	41.89	3.34	18.05
38.00	25.00	1.52	40.21	3.21	17.33
38.00	26.00	1.46	38.67	3.09	16.66
38.00	27.00	1.41	37.24	2.97	16.04
38.00	28.00	1.36	35.91	2.87	15.47
39.00	11.00	3.55	93.80	7.48	40.42
39.00	12.00	3.25	85.98	6.86	37.05
39.00	13.00	3.00	79.37	6.33	34.20
39.00	14.00	2.79	73.70	5.88	31.76
39.00	15.00	2.60	68.79	5.49	29.64
39.00	16.00	2.44	64.49	5.15	27.79
39.00	17.00	2.29	60.69	4.84	26.15
39.00	18.00	2.17	57.32	4.57	24.70
39.00	19.00	2.05	54.31	4.33	23.40
39.00	20.00	1.95	51.59	4.12	22.23
39.00	21.00	1.86	49.13	3.92	21.17
39.00	22.00	1.77	46.90	3.74	20.21
39.00	23.00	1.70	44.86	3.58	19.33
39.00	24.00	1.63	42.99	3.43	18.53
39.00	25.00	1.56	41.27	3.29	17.78
39.00	26.00	1.50	39.69	3.17	17.10
39.00	27.00	1.44	38.22	3.05	16.47
39.00	28.00	1.39	36.85	2.94	15.88
40.00	11.00	3.64	96.21	7.68	41.46
40.00	12.00	3.33	88.19	7.04	38.00
40.00	13.00	3.08	81.41	6.50	35.08
40.00	14.00	2.86	75.59	6.03	32.57
40.00	15.00	2.67	70.55	5.63	30.40
40.00	16.00	2.50	66.14	5.28	28.50
40.00	17.00	2.35	62.25	4.97	26.82
40.00	18.00	2.22	58.79	4.69	25.33
40.00	19.00	2.11	55.70	4.44	24.00
40.00	20.00	2.00	52.91	4.22	22.80
40.00	21.00	1.90	50.39	4.02	21.71
40.00	22.00	1.82	48.10	3.84	20.73
40.00	23.00	1.74	46.01	3.67	19.83
40.00	24.00	1.67	44.09	3.52	19.00
40.00	25.00	1.60	42.33	3.38	18.24
40.00	26.00	1.54	40.70	3.25	17.54
40.00	27.00	1.48	39.20	3.13	16.89
40.00	28.00	1.43	37.80	3.02	16.29
41.00	11.00	3.73	98.61	7.87	42.49
41.00	12.00	3.42	90.39	7.21	38.95
41.00	13.00	3.15	83.44	6.66	35.95
41.00	14.00	2.93	77.48	6.18	33.39
41.00	15.00	2.73	72.31	5.77	31.16
41.00	16.00	2.56	67.80	5.41	29.21
41.00	17.00	2.41	63.81	5.09	27.49
41.00	18.00	2.28	60.26	4.81	25.97
41.00	19.00	2.16	57.09	4.56	24.60
41.00	20.00	2.05	54.24	4.33	23.37
41.00	21.00	1.95	51.65	4.12	22.26
41.00	22.00	1.86	49.31	3.93	21.25
41.00	23.00	1.78	47.16	3.76	20.32
41.00	24.00	1.71	45.20	3.61	19.48
41.00	25.00	1.64	43.39	3.46	18.70
41.00	26.00	1.58	41.72	3.33	17.98
41.00	27.00	1.52	40.17	3.21	17.31
41.00	28.00	1.46	38.74	3.09	16.69
42.00	11.00	3.82	101.02	8.06	43.53
42.00	12.00	3.50	92.60	7.39	39.90
42.00	13.00	3.23	85.48	6.82	36.83
42.00	14.00	3.00	79.37	6.33	34.20
42.00	15.00	2.80	74.08	5.91	31.92
42.00	16.00	2.63	69.45	5.54	29.93
42.00	17.00	2.47	65.36	5.22	28.17
42.00	18.00	2.33	61.73	4.93	26.60
42.00	19.00	2.21	58.48	4.67	25.20
42.00	20.00	2.10	55.56	4.43	23.94
42.00	21.00	2.00	52.91	4.22	22.80
42.00	22.00	1.91	50.51	4.03	21.76
42.00	23.00	1.83	48.31	3.86	20.82
42.00	24.00	1.75	46.30	3.69	19.95
42.00	25.00	1.68	44.45	3.55	19.15
42.00	26.00	1.62	42.74	3.41	18.42
42.00	27.00	1.56	41.15	3.28	17.73
42.00	28.00	1.50	39.69	3.17	17.10
43.00	11.00	3.91	103.42	8.25	44.56
43.00	12.00	3.58	94.80	7.56	40.85
43.00	13.00	3.31	87.51	6.98	37.71
43.00	14.00	3.07	81.26	6.48	35.01
43.00	15.00	2.87	75.84	6.05	32.68
43.00	16.00	2.69	71.10	5.67	30.64
43.00	17.00	2.53	66.92	5.34	28.84
43.00	18.00	2.39	63.20	5.04	27.23
43.00	19.00	2.26	59.88	4.78	25.80
43.00	20.00	2.15	56.88	4.54	24.51
43.00	21.00	2.05	54.17	4.32	23.34
43.00	22.00	1.95	51.71	4.13	22.28
43.00	23.00	1.87	49.46	3.95	21.31
43.00	24.00	1.79	47.40	3.78	20.43
43.00	25.00	1.72	45.51	3.63	19.61
43.00	26.00	1.65	43.76	3.49	18.85
43.00	27.00	1.59	42.13	3.36	18.16
43.00	28.00	1.54	40.63	3.24	17.51
44.00	11.00	4.00	105.83	8.44	45.60
44.00	12.00	3.67	97.01	7.74	41.80
44.00	13.00	3.38	89.55	7.15	38.59
44.00	14.00	3.14	83.15	6.64	35.83
44.00	15.00	2.93	77.61	6.19	33.44
44.00	16.00	2.75	72.76	5.81	31.35
44.00	17.00	2.59	68.48	5.46	29.51
44.00	18.00	2.44	64.67	5.16	27.87
44.00	19.00	2.32	61.27	4.89	26.40
44.00	20.00	2.20	58.20	4.64	25.08
44.00	21.00	2.10	55.43	4.42	23.89
44.00	22.00	2.00	52.91	4.22	22.80
44.00	23.00	1.91	50.61	4.04	21.81
44.00	24.00	1.83	48.50	3.87	20.90
44.00	25.00	1.76	46.56	3.72	20.06
44.00	26.00	1.69	44.77	3.57	19.29
44.00	27.00	1.63	43.11	3.44	18.58
44.00	28.00	1.57	41.57	3.32	17.91
45.00	11.00	4.09	108.23	8.64	46.64
45.00	12.00	3.75	99.21	7.92	42.75
45.00	13.00	3.46	91.58	7.31	39.46
45.00	14.00	3.21	85.04	6.79	36.64
45.00	15.00	3.00	79.37	6.33	34.20
45.00	16.00	2.81	74.41	5.94	32.06
45.00	17.00	2.65	70.03	5.59	30.18
45.00	18.00	2.50	66.14	5.28	28.50
45.00	19.00	2.37	62.66	5.00	27.00
45.00	20.00	2.25	59.53	4.75	25.65
45.00	21.00	2.14	56.69	4.52	24.43
45.00	22.00	2.05	54.12	4.32	23.32
45.00	23.00	1.96	51.76	4.13	22.30
45.00	24.00	1.88	49.61	3.96	21.38
45.00	25.00	1.80	47.62	3.80	20.52
45.00	26.00	1.73	45.79	3.65	19.73
45.00	27.00	1.67	44.09	3.52	19.00
45.00	28.00	1.61	42.52	3.39	18.32
46.00	11.00	4.18	110.64	8.83	47.67
46.00	12.00	3.83	101.42	8.09	43.70
46.00	13.00	3.54	93.62	7.47	40.34
46.00	14.00	3.29	86.93	6.94	37.46
46.00	15.00	3.07	81.13	6.47	34.96
46.00	16.00	2.88	76.06	6.07	32.78
46.00	17.00	2.71	71.59	5.71	30.85
46.00	18.00	2.56	67.61	5.40	29.13
46.00	19.00	2.42	64.05	5.11	27.60
46.00	20.00	2.30	60.85	4.86	26.22
46.00	21.00	2.19	57.95	4.62	24.97
46.00	22.00	2.09	55.32	4.41	23.84
46.00	23.00	2.00	52.91	4.22	22.80
46.00	24.00	1.92	50.71	4.05	21.85
46.00	25.00	1.84	48.68	3.88	20.98
46.00	26.00	1.77	46.81	3.74	20.17
46.00	27.00	1.70	45.07	3.60	19.42
46.00	28.00	1.64	43.46	3.47	18.73
47.00	11.00	4.27	113.04	9.02	48.71
47.00	12.00	3.92	103.62	8.27	44.65
47.00	13.00	3.62	95.65	7.63	41.22
47.00	14.00	3.36	88.82	7.09	38.27
47.00	15.00	3.13	82.90	6.61	35.72
47.00	16.00	2.94	77.72	6.20	33.49
47.00	17.00	2.76	73.14	5.84	31.52
47.00	18.00	2.61	69.08	5.51	29.77
47.00	19.00	2.47	65.45	5.22	28.20
47.00	20.00	2.35	62.17	4.96	26.79
47.00	21.00	2.24	59.21	4.72	25.51
47.00	22.00	2.14	56.52	4.51	24.35
47.00	23.00	2.04	54.06	4.31	23.30
47.00	24.00	1.96	51.81	4.13	22.33
47.00	25.00	1.88	49.74	3.97	21.43
47.00	26.00	1.81	47.83	3.82	20.61
47.00	27.00	1.74	46.05	3.67	19.84
47.00	28.00	1.68	44.41	3.54	19.14
48.00	11.00	4.36	115.45	9.21	49.75
48.00	12.00	4.00	105.83	8.44	45.60
48.00	13.00	3.69	97.69	7.80	42.09
48.00	14.00	3.43	90.71	7.24	39.09
48.00	15.00	3.20	84.66	6.76	36.48
48.00	16.00	3.00	79.37	6.33	34.20
48.00	17.00	2.82	74.70	5.96	32.19
48.00	18.00	2.67	70.55	5.63	30.40
48.00	19.00	2.53	66.84	5.33	28.80
48.00	20.00	2.40	63.50	5.07	27.36
48.00	21.00	2.29	60.47	4.83	26.06
48.00	22.00	2.18	57.72	4.61	24.87
48.00	23.00	2.09	55.21	4.41	23.79
48.00	24.00	2.00	52.91	4.22	22.80
48.00	25.00	1.92	50.80	4.05	21.89
48.00	26.00	1.85	48.84	3.90	21.05
48.00	27.00	1.78	47.03	3.75	20.27
48.00	28.00	1.71	45.35	3.62	19.54
49.00	11.00	4.45	117.85	9.40	50.78
49.00	12.00	4.08	108.03	8.62	46.55
49.00	13.00	3.77	99.72	7.96	42.97
49.00	14.00	3.50	92.60	7.39	39.90
49.00	15.00	3.27	86.43	6.90	37.24
49.00	16.00	3.06	81.02	6.47	34.91
49.00	17.00	2.88	76.26	6.09	32.86
49.00	18.00	2.72	72.02	5.75	31.03
49.00	19.00	2.58	68.23	5.44	29.40
49.00	20.00	2.45	64.82	5.17	27.93
49.00	21.00	2.33	61.73	4.93	26.60
49.00	22.00	2.23	58.93	4.70	25.39
49.00	23.00	2.13	56.36	4.50	24.29
49.00	24.00	2.04	54.02	4.31	23.28
49.00	25.00	1.96	51.86	4.14	22.34
49.00	26.00	1.88	49.86	3.98	21.49
49.00	27.00	1.81	48.01	3.83	20.69
49.00	28.00	1.75	46.30	3.69	19.95
50.00	11.00	4.55	120.26	9.60	51.82
50.00	12.00	4.17	110.24	8.80	47.50
50.00	13.00	3.85	101.76	8.12	43.85
50.00	14.00	3.57	94.49	7.54	40.72
50.00	15.00	3.33	88.19	7.04	38.00
50.00	16.00	3.13	82.68	6.60	35.63
50.00	17.00	2.94	77.81	6.21	33.53
50.00	18.00	2.78	73.49	5.86	31.67
50.00	19.00	2.63	69.62	5.56	30.00
50.00	20.00	2.50	66.14	5.28	28.50
50.00	21.00	2.38	62.99	5.03	27.14
50.00	22.00	2.27	60.13	4.80	25.91
50.00	23.00	2.17	57.51	4.59	24.78
50.00	24.00	2.08	55.12	4.40	23.75
50.00	25.00	2.00	52.91	4.22	22.80
50.00	26.00	1.92	50.88	4.06	21.92
50.00	27.00	1.85	48.99	3.91	21.11
50.00	28.00	1.79	47.24	3.77	20.36

How this calculator works

Each row pairs one chainring with one cassette cog. The ratio is the chainring teeth divided by the cog teeth, and it tells you how many wheel turns follow one crank turn. Multiply by the wheel circumference to get development, the distance covered by one crank turn. Gear inches are an older way to express the same idea: the diameter of an equivalent direct-drive wheel, calculated as the ratio times the wheel diameter in inches. Speed assumes a constant cadence with no coasting or drivetrain losses.

Formula

Gear ratio = chainring teeth / cog teeth. Development = gear ratio x pi x wheel diameter. Gear inches = gear ratio x wheel diameter in inches. Speed (m/s) = cadence / 60 x development. Gear range = largest ratio / smallest ratio.

Worked example

With 34 and 50 tooth chainrings, an 11 to 28 tooth cassette and a 672 mm wheel, the smallest ratio is 34/28 = 1.214 and the largest is 50/11 = 4.545. The range is 3.74, so the top gear is almost four times taller than the climbing gear. The 50/11 gear has development of 9.60 m and, at 90 rpm, a speed of 14.39 m/s or 51.8 km/h.

Frequently asked questions

What does gear range mean?

It is the largest gear ratio divided by the smallest. A range of 3.7 means the hardest gear is 3.7 times taller than the easiest, which is a useful way to compare drivetrains without listing every sprocket.

Why show gear inches as well as development?

Development in metres is easier to picture, while gear inches remain common in English-speaking cycling. They carry the same information once wheel size is fixed.

Are all combinations usable?

On a two-chainring bike, the extreme pairs such as the small chainring with the smallest cog or the large chainring with the largest cog can run the chain at a sharp angle. They still have a valid ratio, but many riders avoid them to reduce wear.

Sources

Written byAmira MansourCalculator writer. Builds and tests Mathulate calculators against published sources.

Reviewed byMarc LefebvreMathematics teacher. Checks each formula and worked example by hand.

Last updated November 1, 2026.