Which countries use mph for speed limits?

The United States, the United Kingdom, and a few smaller territories primarily use mph for road speed limits.

How do I quickly convert mph to kph?

Multiply mph by 1.6 for a quick mental estimate. For example, 60 mph is about 96 kph.

Why do most countries use kph instead of mph?

Most countries adopted the metric system, and kph aligns with that system, making it more consistent internationally.

MPH vs KPH Explained | Speed Limit Conversions for Travelers

If you’ve ever traveled abroad, you’ve probably noticed that road signs can look a little different. In the United States and the United Kingdom, speed limits are posted in miles per hour (mph), while most of the rest of the world uses kilometers per hour (kph). This difference can be confusing for travelers and sometimes even dangerous if not understood. Let’s explore why these two systems exist, how to convert between them, and what it means for drivers on the road.

The Basics: MPH vs KPH

Miles per hour (mph) measures how many miles you travel in one hour. Kilometers per hour (kph) measures how many kilometers you travel in one hour. Since 1 mile equals approximately 1.609 kilometers, mph values are always lower than their equivalent in kph.

Where Are They Used?

MPH: Primarily used in the United States, the United Kingdom, and a handful of smaller nations and territories.
KPH: The standard in most of the world, including Europe, Asia, Australia, Canada, and nearly all of Africa and South America.

This split reflects the broader divide between the imperial and metric systems of measurement. Just like inches vs centimeters, speed measurement differs depending on national standards.

Conversion Formulas

KPH = MPH × 1.609
MPH = KPH ÷ 1.609

For example, a 60 mph speed limit in the US is equivalent to about 97 kph in Europe.

Not in the mood for math? Use our mph to kph converter for quick results.

Conversion Chart

MPH	KPH	Driving Context
30	48	Urban speed limit
55	89	Typical US highway
65	105	Common UK motorway
75	121	High-speed highway

Example Conversion

Suppose you’re driving in Germany and see a sign for 120 kph. What’s that in mph?

120 ÷ 1.609 = 74.5 mph

So 120 kph is roughly 75 mph—a typical high-speed highway limit.

Why the Difference Exists

The reason boils down to the same cultural and historical factors that keep the US tied to imperial units. The mile is an old unit of measurement, and when cars and roads were first standardized in the US and UK, miles per hour became the natural choice. Meanwhile, countries adopting the metric system standardized on kilometers per hour.

Over time, the divide became permanent, with each system deeply embedded in road infrastructure, legal codes, and driver education.

Implications for Travelers

For travelers, this difference is more than academic—it can affect safety. Imagine mistaking a 100 kph limit for 100 mph. That’s the difference between 62 mph and 100 mph, which could result in serious speeding violations or accidents.

Always check whether the country uses mph or kph before driving.
Use rental cars with digital displays that can switch between units.
Rely on converters like our mph to kph tool to double-check limits.

Which System Is Better?

In terms of logic and international consistency, kph makes more sense because it aligns with the metric system. However, mph is still deeply tied to US and UK driving culture. Neither system is going away anytime soon, so the best approach is to be bilingual in speed units.

Conclusion

The mph vs kph divide is another reminder of the broader imperial vs metric debate. For drivers, knowing the difference isn’t just interesting—it’s essential for safety and compliance abroad. Thankfully, converting is easy: just remember 1 mile = 1.609 kilometers. And if you’re ever in doubt, our mph to kph converter will ensure you never get caught speeding by mistake.