The factor
miles = km ÷ 1.609344, or km × 0.621371192237. Five-eighths, 0.625, is a mental shortcut that comes out 0.6% high: 80 km in eighths is 50 miles, against the real 49.71.
Race distances
Rounded to two decimal places:
| Kilometres | Miles |
|---|---|
| 1 km | 0.62 mi |
| 5 km | 3.11 mi |
| 10 km | 6.21 mi |
| 21.0975 km | 13.11 mi |
| 42.195 km | 26.22 mi |
| 50 km | 31.07 mi |
| 100 km | 62.14 mi |
A 5K is 3.11 miles and a 10K 6.21. The half marathon and marathon are defined in kilometres, so their mile figures, 13.11 and 26.22, are the rounded ones.
Questions
How fast is 100 km/h in mph?
62.14 mph. The km/h to mph page has a table of speed limits.
Do UK road signs use km?
No. UK and US road signs give distances in miles and limits in mph. Most other countries use kilometres and km/h.