How to Convert Miles to Kilometers
Converting miles to kilometers is simple: multiply the number of miles by 1.60934. For example, 10 miles × 1.60934 = 16.09 kilometers. To convert kilometers to miles, divide by 1.60934. This conversion factor is exact — one mile is defined as exactly 1,609.344 meters, or 1.609344 kilometers.
The Formula:km = miles × 1.60934 | miles = km ÷ 1.60934
Common Distance Conversions
Whether you're training for a race, planning a road trip, or converting GPS coordinates, these common distance conversions are useful to know:
| Miles | Kilometers | Context |
|---|---|---|
| 0.1 mi | 0.16 km | 100 meters |
| 0.25 mi | 0.4 km | ¼ mile |
| 0.5 mi | 0.8 km | ½ mile |
| 1 mi | 1.61 km | 1 mile |
| 3.11 mi | 5 km | 5K |
| 5 mi | 8.05 km | 5 miles |
| 6.21 mi | 10 km | 10K |
| 10 mi | 16.09 km | 10 miles |
| 13.11 mi | 21.1 km | Half Marathon |
| 26.22 mi | 42.2 km | Marathon |
| 50 mi | 80.47 km | 50 miles |
| 100 mi | 160.93 km | 100 miles |
Running Pace Conversion (min/mile ↔ min/km)
Runners often need to convert pace between miles and kilometers. Use this table to find your equivalent pace:
| Minutes per Mile | Minutes per Kilometer |
|---|---|
| 5:00 | 3:06 |
| 6:00 | 3:44 |
| 7:00 | 4:21 |
| 8:00 | 4:58 |
| 9:00 | 5:35 |
| 10:00 | 6:13 |
| 11:00 | 6:50 |
| 12:00 | 7:27 |
| 13:00 | 8:04 |
| 14:00 | 8:42 |
| 15:00 | 9:19 |
Speed Conversion (mph ↔ km/h)
Convert speed limits and vehicle speeds between miles per hour and kilometers per hour:
| mph | km/h |
|---|---|
| 10 mph | 16.1 km/h |
| 20 mph | 32.2 km/h |
| 30 mph | 48.3 km/h |
| 40 mph | 64.4 km/h |
| 50 mph | 80.5 km/h |
| 60 mph | 96.6 km/h |
| 70 mph | 112.7 km/h |
| 80 mph | 128.7 km/h |
| 90 mph | 144.8 km/h |
| 100 mph | 160.9 km/h |
Quick Estimation Tricks
If you don't have a calculator handy, use these mental math shortcuts:
- Miles to KM: Multiply by 1.6 (slightly underestimate) or add half then add 10% (more accurate)
- KM to Miles: Divide by 1.6 or multiply by 0.6 (rough), or multiply by ⅝ (divide by 8, multiply by 5 — very accurate)
- 5-mile rule: 5 miles ≈ 8 km, 10 miles ≈ 16 km, 20 miles ≈ 32 km
- 60 mph ≈ 100 km/h: Common speed limit conversion
Why the Conversion Factor Is 1.60934
The mile originated in ancient Rome as 1,000 paces (mille passus). The modern international mile was standardized in 1959 as exactly 1,609.344 meters. This definition was agreed upon by the United States, United Kingdom, Canada, Australia, New Zealand, and South Africa, replacing slightly different national definitions that had existed before. The U.S. had used a slightly longer mile (1,609.347 meters) before this agreement, while the British Imperial mile was 1,609.344 meters — the same as the international standard.
Countries That Use Miles vs Kilometers
Miles are the primary unit of distance on road signs in the United States, the United Kingdom, and a few other territories (Liberia, Myanmar). Kilometersare used by every other country in the world, including all of Europe, Asia, Africa, South America, Australia, and New Zealand. Canada uses kilometers on road signs but many Canadians still think of distances in miles informally. The UK officially uses both — miles on road signs but kilometers for many athletic events.