Kilometers to Miles Converter

1 kilometer is about 0.621371 miles. To convert kilometers to miles, divide by 1.609344.

Sources: NIST SP 811, NIST Handbook 44, BIPM SI Brochure Updated October 12, 2026

Result

1 km = 0.621371 mi

Precision

How to convert kilometers to miles

miles = kilometers ÷ 1.609344

1 kilometer is 1,000 meters (SI prefix kilo, 10³). 1 mile is exactly 1,609.344 meters (5,280 feet).

Dividing by 1.609344 is exact. Written as a multiplication the factor is a repeating decimal, 1 km = 0.6213711922373… mi, so a rounded multiplier such as 0.6214 is slightly off. This converter keeps the exact fraction (15625/25146) and rounds only the result it shows.

Worked example: 10 km

Start with the value in kilometers: 10 km.
Divide by 1.609344, because 1 mile = 1.609344 kilometers: 10 ÷ 1.609344 = 6.213711922….
Round to the precision you need: 6.21 mi to two decimals.

Kilometers and miles side by side

Kilometers on top, miles below, lined up with the exact factor. The line marks the value in the converter. Drawn to proportion, not to actual size.

Kilometers to miles chart

Kilometers from 1 to 100 converted to miles with the exact factor, shown to five significant digits.

Kilometers to miles, part 1 of 4
km	mi
1	0.62137
2	1.2427
3	1.8641
4	2.4855
5	3.1069
6	3.7282
7	4.3496
8	4.971
9	5.5923
10	6.2137
11	6.8351
12	7.4565
13	8.0778
14	8.6992
15	9.3206
16	9.9419
17	10.563
18	11.185
19	11.806
20	12.427
21	13.049
22	13.67
23	14.292
24	14.913
25	15.534

Kilometers to miles, part 2 of 4
km	mi
26	16.156
27	16.777
28	17.398
29	18.02
30	18.641
31	19.263
32	19.884
33	20.505
34	21.127
35	21.748
36	22.369
37	22.991
38	23.612
39	24.233
40	24.855
41	25.476
42	26.098
43	26.719
44	27.34
45	27.962
46	28.583
47	29.204
48	29.826
49	30.447
50	31.069

Kilometers to miles, part 3 of 4
km	mi
51	31.69
52	32.311
53	32.933
54	33.554
55	34.175
56	34.797
57	35.418
58	36.04
59	36.661
60	37.282
61	37.904
62	38.525
63	39.146
64	39.768
65	40.389
66	41.01
67	41.632
68	42.253
69	42.875
70	43.496
71	44.117
72	44.739
73	45.36
74	45.981
75	46.603

Kilometers to miles, part 4 of 4
km	mi
76	47.224
77	47.846
78	48.467
79	49.088
80	49.71
81	50.331
82	50.952
83	51.574
84	52.195
85	52.817
86	53.438
87	54.059
88	54.681
89	55.302
90	55.923
91	56.545
92	57.166
93	57.788
94	58.409
95	59.03
96	59.652
97	60.273
98	60.894
99	61.516
100	62.137

miles = kilometers ÷ 1.609344. Factors: NIST SP 811, NIST Handbook 44, BIPM SI Brochure. unitcheck.net/length/kilometers-to-miles/

Common values

Kilometers	Miles	What it is
1 km	0.621371 mi
5 km	3.10686 mi
10 km	6.21371 mi
21.0975 km	13.1094 mi	half marathon
42.195 km	26.2188 mi	marathon
100 km	62.1371 mi

Going the other way? Use the Miles to Kilometers converter.

Frequently asked questions

How many miles are in 1 kilometer?

1 kilometer is about 0.621371 miles. 1 mile is exactly 1,609.344 meters (5,280 feet).

How do I convert kilometers to miles?

Divide by 1.609344: miles = kilometers ÷ 1.609344. For example, 10 km = 6.21 mi.

How many kilometers are in 1 mile?

1 mile is exactly 1.609344 kilometers. To go the other way, use the miles to kilometers converter.

Is the km to mi conversion exact?

The relationship is exact (1 mi = 1.609344 km), but 1 ÷ 1.609344 is a repeating decimal, 0.6213711922…. The converter works with the exact fraction and rounds only the displayed result, so it does not pick up the small error a rounded multiplier would cause.

Sources

NIST Special Publication 811, Guide for the Use of the International System of Units, Appendix B.8: Factors for Units Listed Alphabetically — exact factors are printed in bold in the NIST table (checked October 12, 2026)
NIST Handbook 44 (2026), Appendix C: General Tables of Units of Measurement — US customary units and their exact relationships (checked October 12, 2026)
BIPM, The International System of Units (SI Brochure), 9th edition — defines the SI units, the prefixes and the units accepted for use with the SI