MPH to Km/h Converter
Convert miles per hour to kilometers per hour instantly — exact, free, and no sign-up required.
Runs entirely in your browser — nothing you type is uploaded or stored.
How to convert mph to km/h
To convert miles per hour to kilometers per hour, multiply by 1.609344 — the same exact factor used for miles to kilometers, since both units of time (the hour) are identical and only the distance unit changes.
Worked example: renting a car abroad
A US driver renting a car in Europe sees a motorway speed limit of 130 km/h and wants to know the equivalent in the mph their instincts are calibrated to. Entering 130 into the "From" box (set to km/h, using the swap button) returns about 80.8 mph — useful context for a driver used to US interstate limits typically around 65–80 mph, so the posted limit isn't wildly different from what they're used to, just labelled differently.
Common mistake: assuming "fast" numbers translate directly
Because 1 mph is larger than 1 km/h (roughly 1.6× bigger), a speed limit sign showing "50" means very different things depending on the unit — 50 mph (≈ 80 km/h, a fast rural road) versus 50 km/h (≈ 31 mph, a typical urban limit). Drivers crossing between mph-signed countries (US, UK) and km/h-signed countries (nearly everywhere else) should always confirm which unit a sign is using rather than assuming from the number alone.
Quick reference
| mph | km/h |
|---|---|
| 30 mph | 48.28 km/h |
| 60 mph | 96.56 km/h |
| 70 mph | 112.65 km/h |
| 100 mph | 160.93 km/h |
Need km/h to mph, knots or m/s instead? All Speed units are available in the same dropdown above.
How to use the converter
Three steps. No account, no download, no waiting.
Confirm the units
This page is pre-set to mph to km/h. Change either dropdown any time to switch units or category — every other EngiConvert category is available from the same selector.
Enter your value
Type a number into the "From" box. The result updates instantly as you type — no button to press.
Copy your result
Use the swap button to flip the conversion, or hit "Copy result" to grab the converted value.
Frequently asked questions
What is 1 mph in km/h?
1 mile per hour equals exactly 1.609344 kilometers per hour.
How do I convert mph to km/h quickly?
Multiply by 1.6 for a fast estimate, or use the exact calculator above for a precise figure.
Why do UK road signs use mph but distances change to km elsewhere?
The UK retains mph for speed limits by long-standing convention, even though most of the world — and most engineering — uses SI (metric) units; this is the same historical split that keeps miles on UK road distance signs too.
Why do aircraft use knots instead of mph or km/h?
Knots (nautical miles per hour) tie directly into the latitude/longitude grid used for navigation — one nautical mile corresponds to one minute of latitude — which makes manual and instrument navigation calculations simpler than converting through statute miles or kilometres.
More conversions
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