Open Road
MPH to KM/H Converter: Exact Formula and Quick Table
Convert mph to km/h by multiplying by 1.609344. Convert km/h to mph by dividing by 1.609344. The conversion is exact; the displayed result is rounded to two decimal places. Enter either unit below to convert your own value.
Exact factor: 1 mph = 1.609344 km/h. Result rounded to two decimals.
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One mile defines the conversion
An international mile is 1.609344 kilometres, so a speed in miles per hour uses the same factor. For example, 30 mph is 48.28032 km/h before rounding. Fifty km/h is about 31.07 mph.
Rounding is useful for reading a display, but it is not a new measurement. Converting an inaccurate GPS reading does not make the original reading more accurate.
Quick conversion table
| MPH | KM/H |
|---|---|
| 5 | 8.05 |
| 10 | 16.09 |
| 20 | 32.19 |
| 25 | 40.23 |
| 30 | 48.28 |
| 40 | 64.37 |
| 50 | 80.47 |
| 60 | 96.56 |
| 70 | 112.65 |
Read the label with the number
MPH means miles per hour. KM/H and the KMH label used by some displays mean kilometres per hour. Check the unit on the dashboard and the phone before comparing numbers.
The browser speedometer switches its live speed, maximum and distance together. A saved-drive app may have its own unit setting, so check that display too. Use a passenger or make changes while parked.
Conversion does not establish driving conditions
The table is a unit reference, not a recommendation for a road or a vehicle. For your recorded drives, keep speed in context with the route, elapsed time and reception. Use the average-speed calculator when your question concerns the whole journey rather than one reading.
About this guide
Published by Open Road. Updated 2026-11-03. App screens show example recorded drives.
All driving guides and free toolsQuestions, answered
- What is the mph to km/h formula?
- Multiply mph by 1.609344. The result is kilometres per hour.
- How do I convert km/h to mph?
- Divide km/h by 1.609344. The result is miles per hour.
- Does converting GPS speed change its accuracy?
- No. Unit conversion preserves the same underlying estimate. Reception or measurement error remains in the converted number.
Keep your next drive
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