mph to km/h
Take a UK car across the Channel and the big numbers on the speedometer are still mph, while every sign on the autoroute is in km/h. The converter below gives the km/h figure behind any speed you are used to holding, and the table marks the ones that matter at the wheel.
Last updated: May 2026
Enter a speed in mph to see the km/h equivalent.
From a mph speedometer to km/h road signs
km/h = mph × 1.609344. UK and US speedometers put mph on the main scale, but step off a ferry in Calais or land at a European airport hire desk and every sign switches to km/h with no conversion offered. Multiply the number on your speedometer by 1.609344 and you have the figure the sign is measuring.
Two limits are worth memorizing before the trip: the UK's 70 mph motorway limit sits at 112.65 km/h, and the US 65 mph Interstate limit sits at 104.61 km/h. Both fall short of the 130 km/h standard posted on French and Italian motorways.
Speed limit reference table
| mph | km/h | Typical context |
|---|---|---|
| 20 | 32.2 | Urban residential limit (UK) |
| 30 | 48.3 | Urban speed limit (UK) |
| 40 | 64.4 | Rural road limit (UK) |
| 50 | 80.5 | Dual carriageway / divided highway |
| 60 | 96.6 | Rural road national limit (UK) |
| 65 | 104.6 | Common US Interstate speed limit |
| 70 | 112.7 | UK motorway national speed limit |
| 75 | 120.7 | Higher US Interstate limit (western states) |
Vehicle imports and cross-border driving
UK and US cars have speedometers calibrated in mph. Driving the same car in France means your 70 mph cruise is 112.65 km/h, just under the French 130 km/h motorway limit; your 30 mph suburb limit equals 48.28 km/h, below the European urban standard of 50 km/h. It also matters if the car moves abroad for good: some metric countries require an imported UK car to show km/h on its speedometer before it can be registered locally. Driving a metric car into the UK or US instead? Reach for our km/h to mph converter to translate continental speeds into the local limits.
For EV owners, charging apps and route planners often display vehicle speed in the local convention. A UK-market EV showing a 200-mile range displays roughly 322 km. If your EU trip planner asks for range in km, multiply the displayed miles by 1.609. At 70 mph motorway speed in the UK you are doing 112.7 km/h, which is below the point where energy consumption rises sharply on most EVs (typically 120-130 km/h).
Frequently Asked Questions
What is 70 mph in km/h?
70 mph = 112.65 km/h. This is the UK's national motorway limit, and it sits comfortably under the 130 km/h standard posted on French and Italian autoroutes, so a UK driver keeping to their usual motorway speed is not close to breaking the higher EU limit.
What is 30 mph in km/h?
30 mph = 48.28 km/h. It is the default town limit in England and Scotland, while Wales moved most built-up roads to 20 mph in 2023. The usual urban limit in France and Germany is 50 km/h, so holding 30 mph keeps you just under it, but many town centres there now post 30 km/h zones, which is under 19 mph.
How accurate is the mph times 1.6 shortcut drivers use at the wheel?
Multiplying mph by 1.6 understates the true value by about 0.6%, since the exact factor is 1.609344. At 70 mph the shortcut gives 112 km/h against a true 112.65 km/h, close enough to judge whether you are near a limit, not close enough to argue a speeding ticket.
Why do the UK and US still post speed limits in mph?
Both countries kept mph for road use even after adopting or partially adopting the metric system elsewhere. Road signs, speed cameras and driving tests in both countries work in mph, so cars built for either market show mph as the main speedometer scale, with km/h at most as a smaller inner ring.
My UK car's speedometer leads with mph. What should the needle read on a France or Germany trip?
Work back from the signs to the needle: a 50 km/h town limit is 31 mph, an 80 km/h French country road is just under 50 mph, and the 130 km/h autoroute limit is 80.78 mph, so 80 mph on the needle keeps you legal in dry weather (the limit drops to 110 km/h, about 68 mph, in rain). Germany's recommended 130 km/h on unrestricted Autobahn sections is the same 80.78 mph.