Miles and kilometres are the two main units of distance for road travel, running, and navigation. The USA uses miles; the rest of the world primarily uses kilometres. Here's everything you need to convert between them quickly and accurately.
The Exact Conversion
1 mile = 1.60934 kilometres
1 kilometre = 0.62137 miles
The Formulas
Miles to kilometres:
km = miles × 1.60934
Kilometres to miles:
miles = km ÷ 1.60934
or:
miles = km × 0.62137
Quick Mental Maths
Miles to Kilometres
The Fibonacci trick: The Fibonacci sequence (1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89...) happens to mirror miles-to-kilometres conversions almost exactly:
- 1 mile ≈ 1.6 km (next Fibonacci number: 1 → 2... close)
- 3 miles ≈ 5 km ✓
- 5 miles ≈ 8 km ✓
- 8 miles ≈ 13 km ✓
- 13 miles ≈ 21 km ✓
The ×1.6 method: Multiply miles by 1.6 for a fast approximation.
10 miles × 1.6 = 16 km (exact: 16.09 km) — less than 1% error
Kilometres to Miles
Divide by 1.6 (or multiply by 0.6):
100 km ÷ 1.6 = 62.5 miles (exact: 62.14 miles)
Or use the Fibonacci trick in reverse:
- 5 km ≈ 3 miles ✓
- 8 km ≈ 5 miles ✓
- 13 km ≈ 8 miles ✓
Conversion Table
| Miles | Kilometres | Context |
|---|---|---|
| 0.25 mi | 0.4 km | Short walk |
| 0.5 mi | 0.8 km | — |
| 1 mi | 1.609 km | 1 mile |
| 1.5 mi | 2.414 km | — |
| 2 mi | 3.219 km | — |
| 3 mi | 4.828 km | — |
| 5 mi | 8.047 km | — |
| 6.2 mi | 10 km | 10K run |
| 10 mi | 16.09 km | — |
| 13.1 mi | 21.09 km | Half marathon |
| 20 mi | 32.19 km | — |
| 26.2 mi | 42.19 km | Marathon |
| 50 mi | 80.47 km | — |
| 60 mi | 96.56 km | Approx 100 km |
| 100 mi | 160.93 km | Century ride |
| 500 mi | 804.67 km | — |
Common Running Distances Converted
| Distance | Miles | Kilometres |
|---|---|---|
| Parkrun | 3.1 mi | 5 km |
| 10K | 6.21 mi | 10 km |
| 15K | 9.32 mi | 15 km |
| 10 miles | 10 mi | 16.09 km |
| Half marathon | 13.11 mi | 21.10 km |
| 25K | 15.53 mi | 25 km |
| 30K | 18.64 mi | 30 km |
| Marathon | 26.22 mi | 42.19 km |
| 50K ultra | 31.07 mi | 50 km |
| 100K ultra | 62.14 mi | 100 km |
Driving Distances: Major Routes
| Journey | Miles | Kilometres |
|---|---|---|
| London to Edinburgh | 414 mi | 667 km |
| London to Paris (driving) | 287 mi | 462 km |
| New York to Boston | 215 mi | 346 km |
| New York to Los Angeles | 2,790 mi | 4,490 km |
| Sydney to Melbourne | 545 mi | 877 km |
Speed Conversion: mph to km/h
Speed limits are in mph in the USA and UK, km/h elsewhere.
km/h = mph × 1.60934
mph = km/h ÷ 1.60934
| mph | km/h | Context |
|---|---|---|
| 20 mph | 32 km/h | Urban limit (UK) |
| 30 mph | 48 km/h | Urban limit (UK/US) |
| 50 mph | 80 km/h | — |
| 60 mph | 97 km/h | UK single carriageway |
| 70 mph | 113 km/h | UK motorway |
| 100 km/h | 62 mph | Motorway (EU) |
| 120 km/h | 75 mph | Motorway (DE, ES) |
| 130 km/h | 81 mph | Motorway (FR, IT) |
Why Different Systems?
The mile traces back to the Roman mille passuum — "a thousand paces" — where one pace was two steps (roughly 1.48 metres). The exact length was standardised later.
The kilometre was defined during the French Revolution as one ten-thousandth of the distance from the equator to the North Pole — an intentionally rational, science-based measurement. This system (the metric system) was adopted globally for science and, eventually, everyday life in most countries.
The USA, Myanmar, and Liberia are the only countries that have not officially adopted the metric system for everyday use.
Quick Reference Card
Miles → km: multiply by 1.6 (or exactly 1.60934)
km → miles: multiply by 0.62 (or exactly 0.62137)
3 miles ≈ 5 km
5 miles ≈ 8 km
Half marathon = 13.1 miles = 21.1 km
Marathon = 26.2 miles = 42.2 km