What this does
Converts miles to kilometers live. Multiply by exactly 1.609344 — that's the whole formula, km = miles × 1.609344, because the international mile has been defined as 1,609.344 meters since 1959. The page starts with 1 mile = 1.609344 km already filled in. Type in either box and the other follows keystroke by keystroke; the ⇄ button swaps the two units and keeps the left-hand number. Results are rounded to six decimals. No server is involved, so it works offline.
Common mile distances in kilometers
| Miles | Kilometers | Context |
|---|---|---|
| 1 | 1.609344 | four laps of a 400 m track, plus 9 m |
| 3 | 4.828032 | a "3-mile" training loop, just under a 5K |
| 13.1 | 21.082406 | half marathon, rounded American style |
| 26.2 | 42.164813 | marathon as printed on bumper stickers |
| 55 | 88.51392 | a US state highway limit (mph) |
| 100 | 160.9344 | a comfortable day's drive between stops |
| 275 | 442.5696 | EPA range of a mid-size EV |
| 2,500 | 4,023.36 | roughly New York to Los Angeles by road |
How do I estimate miles to km without a calculator?
Add 60 percent. Take the miles, add half, then add a tenth: 20 miles → 20 + 10 + 2 = 32 km (real 32.2). For round numbers, "miles × 8 ÷ 5" is exact to within half a percent: 5 miles ≈ 8 km, 25 miles ≈ 40 km, 50 miles ≈ 80 km. This is the direction where the number grows, so if your estimate came out smaller than the miles you started with, you divided instead of multiplying.
How do I convert a running pace from min/mile to min/km?
Pace is time per distance, so it goes the opposite way to distance: divide by 1.609344. An 8:00 min/mile pace is 8 ÷ 1.609344 = 4.971 minutes per km, which is 4 min 58 s. A 10:00 min/mile is 6:13 min/km, and a 7:00 min/mile is 4:21. Do the arithmetic in decimal minutes first, then turn the fraction back into seconds by multiplying by 60. This matters when you set a metric watch to a US training plan — or when a European coach hands you paces per kilometer.
Are 26.2 miles and 42.195 km really the same distance?
Not quite. The marathon is defined as 42.195 km, which is 26.21876 miles. Round that to 26.2 and convert back and you get 42.164813 km — about 30 meters short. That's the worked example for this tool's rounding: type 26.2 and the right-hand box shows 42.164813, six decimals with nothing hidden. For a race you'll never notice 30 m; for a certified course measurement you would, which is why courses are measured in meters, not miles.
Is a nautical mile the same as a mile?
No. A nautical mile is exactly 1,852 m — 1.150779 statute miles — and it's what ships, aircraft and weather services mean, along with knots for speed. This page converts the statute mile used on road signs and odometers. If you have a flight distance or a sailing passage in nautical miles, pick "Nautical miles" in the left dropdown; every length unit is available here even though the category tabs are hidden. The full converter adds knots on its Speed tab.
Where does miles-to-km come up in real life?
Planning a European or Canadian road trip from US or UK map distances, entering your car's mileage on a rental or insurance form abroad, reading a metric-only running app, and matching a guidebook's mile markers to a trail's kilometer posts. The reverse — reading a foreign road sign and thinking in miles — is covered on the km to miles page.