Written by Muneeb Rana · Last updated 26 October 2026
Quick answer: To convert kmh to mph, divide the speed in kilometres per hour by 1.609344, or multiply by about 0.621371. So 100 km/h is 62.14 mph, 50 km/h is 31.07 mph and 120 km/h is 74.56 mph. Type any value in the converter for an instant answer, or use the table below for common road speeds.
TL;DR
- mph = km/h ÷ 1.609344.
- Shortcut: multiply by 0.6, then add a bit.
- 100 km/h ≈ 62 mph.
- Exact factor comes from the defined international mile.
- Full table below.
KMH to MPH formula
The international mile is exactly 1,609.344 metres, so one mile per hour equals 1.609344 km/h. To go from km/h to mph, divide by 1.609344. NIST lists the same factor in its unit conversion resources. Our converter rounds to two decimals.
Mental shortcut
Multiply by 6, drop the last digit, then add about 3%. Example: 80 km/h × 6 = 480 → 48, plus a little ≈ 49.7 mph. Or halve the number and add a fifth of the half: 100 → 50 + 10 + 2 ≈ 62. Good enough to sanity-check a road sign.
Conversion table
| km/h | mph |
|---|---|
| 10 | 6.2 |
| 20 | 12.4 |
| 30 | 18.6 |
| 40 | 24.9 |
| 50 | 31.1 |
| 60 | 37.3 |
| 70 | 43.5 |
| 80 | 49.7 |
| 90 | 55.9 |
| 100 | 62.1 |
| 110 | 68.4 |
| 120 | 74.6 |
| 130 | 80.8 |
| 140 | 87.0 |
| 150 | 93.2 |
| 160 | 99.4 |
| 170 | 105.6 |
| 180 | 111.8 |
| 190 | 118.1 |
| 200 | 124.3 |
Common limits abroad
Many European urban limits are 50 km/h (31 mph) and motorway limits are often 120–130 km/h (75–81 mph); Germany's Autobahn has advisory sections. In Canada, highways are typically 100 km/h (62 mph). Always check local signs. More in mph vs km/h.
Quick mental shortcut
Multiply km/h by 6 and divide by 10 for a close estimate: 100 km/h → 60 mph (exact: 62.1). The shortcut slightly under-states the mph, so for limits allow a bit of margin.
Skip the maths
Speedometer PRO can display MPH or KM/H directly, so you can match local signs without converting in your head.
Related: Free speed tools · MPH guide: speed units explained · MPH to KMH converter · MPH vs km/h · Speedometer MPH and KM/H units · Knots to MPH converter · MPH to meters per second converter · What does mph mean?
Get Speedometer PRO on Google Play · Download on the App Store · Set it up before you move; never handle your phone while driving.
Sources
- Unit conversion (NIST Office of Weights and Measures): nist.gov (accessed 26 October 2026)
- Miles per hour (Wikipedia): en.wikipedia.org (accessed 26 October 2026)
- Kilometres per hour (Wikipedia): en.wikipedia.org (accessed 26 October 2026)
FAQ
How do I convert km/h to mph?
Divide by 1.609344, or multiply by 0.621371. For example, 90 km/h divided by 1.609344 is 55.9 mph.
What is 100 km/h in mph?
100 km/h is 62.14 mph. That is a common highway limit in Canada and Australia, and a handy anchor for other conversions.
What is 120 km/h in mph?
120 km/h is 74.56 mph, roughly the 75 mph limit some US states use on rural interstates.
Is kph the same as km/h?
Yes. Kph, kmh and km/h all mean kilometres per hour; km/h is the standard SI-style symbol.
Why 1.609344 exactly?
Since 1959 the international yard has been defined as exactly 0.9144 m, which makes a mile exactly 1,609.344 m and fixes the factor.