Written by Muneeb Rana · Last updated 26 October 2026
Quick answer: Speedometer PRO shows speedometer MPH or KM/H readings and lets you switch between them. One mile per hour is exactly 1.609344 kilometres per hour, so 60 mph is about 96.6 km/h. Use the unit that matches the road signs where you are driving, which is especially useful in a rental car abroad.
TL;DR
- Toggle between MPH and KM/H.
- 1 mph = 1.609344 km/h exactly.
- Match the unit on local road signs.
- Distance follows the unit choice.
- Knots are not offered in the current version.
How the conversion works
The international mile is defined as exactly 1,609.344 metres, so 1 mph equals 1.609344 km/h, and 1 km/h is about 0.621 mph. Your phone reports speed in metres per second; the app multiplies by 2.23694 for mph or by 3.6 for km/h. Our km/h to mph and mph to km/h tools show full tables.
Who uses which
The United States and the United Kingdom post speed limits in miles per hour, along with a few other territories. Most of the world, including Canada, Australia and continental Europe, uses kilometres per hour. See mph vs km/h for the history.
Speedometer MPH tips for travel
Driving a UK car in France, or an American visitor in Canada, means reading the small secondary scale on the dash. Switching the app to the local unit gives you a big readout that matches the signs. Remember that 50 km/h is about 31 mph and 100 km/h about 62 mph.
Distance units
Trip and odometer distances follow the speed unit: miles with MPH, kilometres with KM/H.
Switching while abroad
Change units when you cross a border, before you drive, so the reading matches signs.
Rounding
Displays round to whole numbers; tiny differences between apps can come from rounding.
Other units
Boaters and pilots use knots, and scientists use metres per second. The app does not offer them today; use our knots to mph and mph to m/s converters.
Related: MPH guide: speed units explained · MPH vs km/h · KMH to MPH converter · MPH to KMH converter · What does mph mean? · Speedometer app features
Get Speedometer PRO on Google Play · Download on the App Store · Set it up before you move; never handle your phone while driving.
Sources
- Speedometer PRO・MPH Tracker (Google Play listing): play.google.com (accessed 26 October 2026)
- Speedometer PRO・MPH Tracker (App Store listing): apps.apple.com (accessed 26 October 2026)
- 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 switch to KM/H?
Change the unit in the app's settings or on the speed screen, ideally before you start moving. The display and trip distances then use the new unit.
Is the default MPH?
We have not confirmed whether the default depends on your region. Check the unit on first launch and change it if needed.
Does the app support knots?
No, the current version offers MPH and KM/H only. Our free knots to mph converter covers boating and aviation speeds in the meantime.
What is 100 km/h in mph?
About 62.1 mph, because 100 divided by 1.609344 is 62.14. A quick mental rule is to multiply km/h by 0.6 and add a little.
Does changing units affect accuracy?
No. The underlying GPS speed is the same; only the display multiplier changes between mph and km/h.