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Convert km/h to mph

1 kilometer per hour equals 0.62137119 miles per hour. Enter a value below to convert instantly.

Kilometres per hour to miles per hour converts the speed limits, vehicle specifications and weather reports used across most of the world into US and UK terms. Multiply by 0.621371 — or use the five-eighths mental shortcut for a quick, slightly high estimate.

1 km/h
0.62137119 mph

Multiply the number of kilometers per hour by 0.621371192237 to get miles per hour. How this is calculated

Copy link puts your number after the #, which browsers never send to a server — but the link itself carries it, so anyone you send it to sees the value. Save keeps the unit pair in this browser only; clear it any time from your saved list.

Need the other direction? Convert mile per hour to kilometer per hour →

Formula

Multiply the number of kilometers per hour by 0.621371192237 to get miles per hour.

Step by step

  1. Start with 1 km/h.
  2. Multiply by the conversion factor 0.621371192237.
  3. 1 × 0.621371192237 = 0.62137119 mph.

Kilometers per Hour to Miles per Hour conversion table

Kilometers per Hour (km/h) Miles per Hour (mph)
1 0.62137119
5 3.106856
10 6.2137119
20 12.427424
30 18.641136
40 24.854848
50 31.06856
60 37.282272
80 49.709695
100 62.137119

Where kilometers per hour and miles per hour are used together

Driving abroad

A 130 km/h motorway limit is 81 mph and a 70 mph limit is 113 km/h. Cars sold in one market and driven in another often have both scales on the dial, with the secondary one in smaller figures.

Weather and storm reports

Wind speeds are published in mph, km/h and knots simultaneously by meteorological agencies — the Saffir-Simpson hurricane scale lists all three for every category, which makes it a convenient cross-check on any conversion.

Vehicle performance figures

0–60 mph and 0–100 km/h are the two standard acceleration benchmarks, and they are not the same test: 60 mph is 96.6 km/h, so a 0–100 km/h time is always slightly longer than the same car's 0–60 mph time.

Cycling and running pace

Speed in km/h converts directly, but pace — minutes per kilometre or per mile — is a reciprocal and does not. A 10 km/h run is 6:00 per km but 9:39 per mile.

Everyday kilometers per hour worth knowing

Values people actually look up, with the reason each one comes up. Every figure is calculated with the same engine as the converter above.

Kilometer per Hour (km/h) Mile per Hour (mph) What it is
30 18.641136 An urban limit
50 31.06856 A common city limit
80 49.709695 A rural road limit
100 62.137119 The standard acceleration benchmark
110 68.350831 A motorway limit
120 74.564543 A motorway limit
130 80.778255 A European motorway limit
200 124.27424 A round figure

How these two units are defined

Both units are a distance divided by an hour, so only the distance definition differs: exactly 1,609.344 m per mile against 1,000 m per kilometre. Speedometers are a separate matter — regulations in most markets allow a speedometer to over-read but never under-read, so a dashboard showing 100 km/h often means an actual 95–98 km/h. That tolerance is larger than any rounding in this conversion.

Rounding and precision

The factor is exact. Speed limits are set in round numbers in whichever system the country uses, so a converted limit is never round — 70 mph is 112.65 km/h. Quote converted limits to the nearest whole unit and remember that enforcement thresholds, speedometer tolerance and GPS lag all exceed the conversion's precision by a wide margin.

Mistakes people make with this conversion

  • Converting pace as if it were speed

    Minutes per mile and minutes per kilometre are reciprocals of speed. A 6:00/km pace is 9:39/mile, not 3:44 — you divide by 0.621371 rather than multiply.

  • Assuming 100 km/h and 60 mph are equal

    They differ by 3.5%: 60 mph is 96.6 km/h. It is close enough for conversation and not close enough for a performance comparison.

  • Trusting the speedometer as the true speed

    Type approval in most markets permits a speedometer to read high. The indicated figure is usually a few percent above actual, which dwarfs any conversion rounding.

Read more about these units

Sources for this page

  1. Special Publication 811 — Guide for the Use of the International System of Units (SI) NIST (US National Institute of Standards and Technology) · Conversion factors between US customary and SI units, and the rounding and significant-figure conventions this site follows.
  2. Saffir-Simpson Hurricane Wind Scale NOAA National Hurricane Center · A worked example of the same wind speed published simultaneously in mph, knots, and km/h.

Content on this page last reviewed 12 August 2026. Spotted an error? Report it — see also how these values are calculated.

Convert Kilometer per Hour to other speed units

1 km/h expressed in every other speed unit on this site.

  • Meter per Second m/s 0.27777778
  • Kilometer per Minute km/min 0.016666667
  • Kilometer per Second km/s 0.00027777778
  • Meter per Minute m/min 16.666667
  • Meter per Hour m/h 1,000
  • Centimeter per Second cm/s 27.777778
  • Centimeter per Minute cm/min 1,666.6667
  • Centimeter per Hour cm/h 100,000
  • Millimeter per Second mm/s 277.77778
  • Millimeter per Minute mm/min 16,666.667
  • Millimeter per Hour mm/h 1,000,000
  • Mile per Hour mph 0.62137119
  • Mile per Minute mi/min 0.010356187
  • Mile per Second mi/s 0.00017260311
  • Yard per Hour yd/h 1,093.6133
  • Yard per Minute yd/min 18.226888
  • Yard per Second yd/s 0.30378147
  • Foot per Hour ft/h 3,280.8399
  • Foot per Minute ft/min 54.680665
  • Foot per Second ft/s 0.91134442
  • Inch per Second in/s 10.936133
  • Inch per Minute in/min 656.16798
  • Inch per Hour in/h 39,370.079
  • Knot kn 0.5399568
  • Knot (UK) kn (UK) 0.53961182
  • Mach (sea level) M 0.00081629721
  • Mach (SI standard) M (SI) 0.0009414715
  • Mach (20 °C, 1 atm) M (20 °C) 0.00080843358
  • Speed of Sound (pure water) c (H₂O) 0.00018734591
  • Speed of Sound (sea water) c (sea) 0.00018255637
  • Speed of Light (vacuum) c 9.2656693e-10
  • Cosmic Velocity (first) v₁ 0.000035161744
  • Cosmic Velocity (second) v₂ 0.000024801587
  • Cosmic Velocity (third) v₃ 0.000016663334
  • Earth's Orbital Velocity v⊕ 0.0000093323628

About the kilometer per hour

The kilometer per hour (km/h) is a Metric unit of speed.

About the mile per hour

The mile per hour (mph) is a Imperial unit of speed.

Related conversions

Frequently asked questions

What is 100 km/h in mph?

100 km/h is 62.14 mph. It is the most common motorway limit worldwide and sits between the US 55 and 65 mph limits.

Is there a mental shortcut?

Multiply by 5 and divide by 8: 80 km/h × 5 ÷ 8 = 50 mph against a true 49.7 mph. The shortcut runs about half a percent high, which is fine for reading a road sign.

How do knots fit in?

A knot is one nautical mile per hour, exactly 1.852 km/h. It is used for marine and aviation speeds and for wind, and it is about 15% faster than a statute mile per hour.

How many miles per hour are in a kilometer per hour?

One kilometer per hour equals 0.62137119 miles per hour.

How do you convert kilometers per hour to miles per hour?

Multiply the number of kilometers per hour by 0.621371192237 to get miles per hour.

What is 1 mile per hour in kilometers per hour?

One mile per hour equals 1.609344 kilometers per hour.

When would I convert kilometers per hour to miles per hour?

This conversion is common when driving, running, cycling, aviation, and weather reports.