Free MPH to KM/H Converter

Convert speed between miles per hour and kilometers per hour. Type in either box for an instant result, and scan the table for common speed limits.

Miles per hour (mph)

Kilometers per hour (km/h)

Common values

Miles per hour	Kilometers per hour
10 mph	16.09 km/h
20 mph	32.19 km/h
30 mph	48.28 km/h
50 mph	80.47 km/h
60 mph	96.56 km/h
70 mph	112.65 km/h
100 mph	160.93 km/h

Quick answer

To convert miles per hour to kilometers per hour, multiply by 1.609344, because one mile is 1.609344 km. For example, 60 mph = 96.56 km/h. To convert km/h back to mph, divide by 1.609344 (or multiply by 0.621371).

Formula & method

km/h = mph × 1.609344

mph — speed in miles per hour
1.609344 — kilometres in one mile (exact)

Inverse: mph = km/h × 0.621371.

Examples

Example 1: A 30 mph limit

Input: 30 mph
Result: 48.28 km/h
Why: 30 × 1.609344 = 48.28.

Example 2: Highway speed

Input: 60 mph
Result: 96.56 km/h
Why: 60 × 1.609344 = 96.56.

Example 3: 100 mph

Input: 100 mph
Result: 160.93 km/h
Why: 100 × 1.609344 = 160.93.

When to use this tool

Reading a speedometer or speed limit in the other unit while driving abroad.
Comparing vehicle top speeds across regions.
Converting pace and speed for sports or fitness.

Common mistakes

Using 1.6 for exact work. The precise factor is 1.609344.
Reversing the direction — mph × 1.609 gives km/h; km/h × 0.621 gives mph.
Assuming speed limits convert to round numbers; 50 mph is 80.5 km/h, not exactly 80.

Frequently asked questions

＋ How do I convert mph to km/h?

Multiply the speed in mph by 1.609344. For a rough estimate, multiply by 1.6.

＋ How do I convert km/h to mph?

Divide the km/h value by 1.609344, or multiply by 0.621371. You can also type into the km/h box here.

＋ What is 100 km/h in mph?

About 62.1 mph (100 × 0.621371).

＋ Why isn’t the conversion a round number?

Because a mile and a kilometre aren’t simple multiples of each other, most speed conversions land on decimals.

＋ Is this the same factor as miles to kilometers?

Yes. Speed is just distance over time, so mph to km/h uses the same 1.609344 factor as miles to kilometers.

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Last updated: 2026-06-05How we calculate Report a correction Disclaimer

Provided “as is” for general information only — results may be inaccurate, so verify before you rely on them. No warranty; use at your own risk.