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Speed Unit Converter

MPH to KM/H Converter

Instantly convert between miles per hour and kilometers per hour. Free online converter with common speed conversions and formula explanation.

Quick Conversion Formulas
MPH to KM/H: Multiply by 1.60934
KM/H to MPH: Multiply by 0.621371

Convert Speed Units

Enter a value in either field to convert automatically

Common MPH to KM/H Conversions

Quick reference table for frequently searched speed conversions

MPHKM/HContext
3.1 mph4.99 km/hWalking pace
5 mph8.05 km/hBrisk walk
10 mph16.09 km/hJogging
15 mph24.14 km/hCycling
20 mph32.19 km/hCity driving
25 mph40.23 km/hResidential area
27.8 mph44.74 km/hUsain Bolt top speed
30 mph48.28 km/hUrban speed limit
35 mph56.33 km/hSuburban road
40 mph64.37 km/hMain road
45 mph72.42 km/hHighway on-ramp
50 mph80.47 km/hRural road
55 mph88.51 km/hUS highway
60 mph96.56 km/hHighway
65 mph104.61 km/hUS Interstate
70 mph112.65 km/hMotorway
75 mph120.70 km/hUS Interstate max
80 mph128.75 km/hAutobahn advisory
85 mph136.79 km/hHigh speed limit
100 mph160.93 km/hSports car
120 mph193.12 km/hFast driving
150 mph241.40 km/hSupercar
200 mph321.87 km/hRace car
250 mph402.33 km/hFormula 1
767 mph1234.36 km/hSpeed of sound

Common KM/H to MPH Conversions

KM/HMPHContext
5 km/h3.11 mphWalking
10 km/h6.21 mphBrisk walk
20 km/h12.43 mphJogging
30 km/h18.64 mphCity limit
50 km/h31.07 mphUrban area
60 km/h37.28 mphSuburban
80 km/h49.71 mphRural road
100 km/h62.14 mphHighway
110 km/h68.35 mphMotorway
120 km/h74.56 mphAutobahn
130 km/h80.78 mphFast motorway
150 km/h93.21 mphSports car
200 km/h124.27 mphSupercar
250 km/h155.34 mphHigh performance
300 km/h186.41 mphRace car

Conversion Formula

The conversion between miles per hour (mph) and kilometers per hour (km/h) is based on the relationship between miles and kilometers:

MPH to KM/H
km/h = mph × 1.60934

Since 1 mile = 1.60934 kilometers

KM/H to MPH
mph = km/h × 0.621371

Since 1 kilometer = 0.621371 miles

Understanding MPH and KM/H

Miles per hour (mph) is primarily used in the United States, United Kingdom, and a few other countries. It's based on the imperial/US customary system where 1 mile equals 5,280 feet.

Kilometers per hour (km/h) is used by the majority of the world and is part of the metric system. It's the standard unit for speed limits and vehicle speedometers in most countries.

Countries Using MPH

United States, United Kingdom, Myanmar, Liberia, and some Caribbean nations

Frequently Asked Questions

Common questions about mph to km/h conversion

How do you convert mph to km/h?

To convert miles per hour (mph) to kilometers per hour (km/h), multiply the mph value by 1.60934. For example, 60 mph × 1.60934 = 96.56 km/h.

What is 60 mph in km/h?

60 mph equals 96.56 km/h. This is a common highway speed in the United States.

What is 100 km/h in mph?

100 km/h equals 62.14 mph. This is a common speed limit on highways in many countries.

What is 3.1 mph in km/h?

3.1 mph equals approximately 4.99 km/h (about 5 km/h). This is the average human walking speed.

What is 27.8 mph in km/h?

27.8 mph equals approximately 44.74 km/h. This is Usain Bolt's top speed during his 100m world record.

Why do some countries use mph and others use km/h?

The United States, United Kingdom, and a few other countries use miles per hour (mph) based on the imperial system. Most of the world uses kilometers per hour (km/h) based on the metric system, which was adopted internationally for its simplicity and decimal-based calculations.