Convert km/h to mph

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Type a speed in kilometers per hour and the result in miles per hour appears as you type. At 100 km/h the converter shows 62.1371 mph, because one mile per hour is exactly 1.609344 km/h.

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What is a kilometer per hour and what is a mile per hour?

A kilometer per hour describes the speed at which you cover one kilometer in one hour. Its symbol is km/h[1].


In English you will also see the abbreviations kph, kmph and km/hr[1]. They all name the same unit, so a value written kph goes into the converter exactly as it is.


A mile per hour (mph) measures the same kind of speed in statute miles. One mile per hour is exactly 1.609344 km/h[2].


That figure is exact because it comes straight from the length of the mile. A mile is 1,760 yards long, and since 1 July 1959 it has measured exactly 1.609344 kilometers[3].


Miles per hour are used in the United States, in the United Kingdom and in a number of smaller countries and territories with close ties to either of them[2]. That is why the conversion comes up on almost any trip from one of those countries to a place where signs show km/h.

White ICE high-speed train with a red stripe on tracks under overhead wires
An ICE high-speed train leaves Frankfurt am Main central station. Photo: Nico Ruge, Unsplash.

How many mph is 100 km/h?

100 km/h is 62.14 mph. To convert km/h to mph, divide the speed in kilometers per hour by 1.609344.


The same division turns a metric road sign into miles per hour. In Quebec the default limit in cities, towns and villages is 50 km/h[4]. Converted, that is 31.07 mph. On a gravel road the default limit is 70 km/h. In miles per hour that comes to 43.5 mph. On an autoroute you drive at no more than 100 km/h and no less than 60 km/h, and the lower figure is 37.28 mph.


The sum is useful behind the wheel of a car with an mph speedometer, when you need to find the limit from a metric sign on the dial.


Formula: mph = km/h ÷ 1.609344


The result is exact, because 1.609344 follows directly from the length of the mile. At road speeds, multiplying by 0.621371 gives the same answer to four decimal places. The converter shows four decimal places, and the tables round to hundredths.

How to convert 120 km/h to mph: formula and example

The formula has a single step: mph = km/h ÷ 1.609344.


Take 120 km/h, the motorway limit in Ireland[5]. Dividing it by 1.609344 gives 74.56 mph. On a dial marked in miles per hour, you look just short of 75.


For a figure you can work out in your head, split the sum into two steps. First divide the speed by 8. Then multiply the result by 5. For 120 km/h the first step gives 15, and the second gives 75 mph.


This shortcut assumes a mile of 1.6 kilometers, so the result comes out about 0.6% too high. At 120 km/h the gap is less than half a mile per hour.


The mph to km/h converter handles the reverse conversion. Distances use the same divisor, so kilometers from a map turn into miles with the km to miles converter.

Black and white car speedometer with a large miles per hour scale up to 140 and a smaller inner kilometers per hour scale up to 220
The outer scale of this speedometer shows miles per hour up to 140, and the smaller inner scale shows kilometers per hour up to 220. On a dial like this you read a km/h limit without converting it. Photo: Nick Fewings, Unsplash.

How many mph is a given speed in km/h?

Speeds from 1 to 1,000 km/h, with the result in miles per hour and in meters per second.
Kilometers per hourMiles per hour (mph)Meters per second (m/s)
1 km/h0.62 mph0.28 m/s
3 km/h1.86 mph0.83 m/s
5 km/h3.11 mph1.39 m/s
10 km/h6.21 mph2.78 m/s
15 km/h9.32 mph4.17 m/s
20 km/h12.43 mph5.56 m/s
25 km/h15.53 mph6.94 m/s
30 km/h18.64 mph8.33 m/s
35 km/h21.75 mph9.72 m/s
40 km/h24.85 mph11.11 m/s
45 km/h27.96 mph12.5 m/s
50 km/h31.07 mph13.89 m/s
55 km/h34.18 mph15.28 m/s
60 km/h37.28 mph16.67 m/s
65 km/h40.39 mph18.06 m/s
70 km/h43.5 mph19.44 m/s
75 km/h46.6 mph20.83 m/s
80 km/h49.71 mph22.22 m/s
85 km/h52.82 mph23.61 m/s
90 km/h55.92 mph25 m/s
95 km/h59.03 mph26.39 m/s
100 km/h62.14 mph27.78 m/s
105 km/h65.24 mph29.17 m/s
110 km/h68.35 mph30.56 m/s
115 km/h71.46 mph31.94 m/s
120 km/h74.56 mph33.33 m/s
125 km/h77.67 mph34.72 m/s
130 km/h80.78 mph36.11 m/s
135 km/h83.89 mph37.5 m/s
140 km/h86.99 mph38.89 m/s
145 km/h90.1 mph40.28 m/s
150 km/h93.21 mph41.67 m/s
160 km/h99.42 mph44.44 m/s
170 km/h105.63 mph47.22 m/s
180 km/h111.85 mph50 m/s
190 km/h118.06 mph52.78 m/s
200 km/h124.27 mph55.56 m/s
220 km/h136.7 mph61.11 m/s
240 km/h149.13 mph66.67 m/s
250 km/h155.34 mph69.44 m/s
280 km/h173.98 mph77.78 m/s
300 km/h186.41 mph83.33 m/s
320 km/h198.84 mph88.89 m/s
330 km/h205.05 mph91.67 m/s
350 km/h217.48 mph97.22 m/s
360 km/h223.69 mph100 m/s
370 km/h229.91 mph102.78 m/s
400 km/h248.55 mph111.11 m/s
450 km/h279.62 mph125 m/s
500 km/h310.69 mph138.89 m/s
600 km/h372.82 mph166.67 m/s
700 km/h434.96 mph194.44 m/s
800 km/h497.1 mph222.22 m/s
1,000 km/h621.37 mph277.78 m/s
The meters per second column divides the speed in km/h by 3.6. An hour has 3,600 seconds and a kilometer has 1,000 meters, which is where that number comes from.

What are Quebec speed limits in mph?

Default limits set by the Quebec government for roads with no sign showing another limit, converted to miles per hour.
RoadLimit in km/hLimit in mph
Cities, towns and villages50 km/h31.07 mph
Autoroutes, minimum speed60 km/h37.28 mph
Gravel roads70 km/h43.5 mph
Autoroutes, maximum speed100 km/h62.14 mph
The values come from the Quebec government page on speed limits[4] and apply where no sign shows a different limit. Every speed limit sign in Canada was changed from mph to km/h over the Labour Day weekend in 1977[6].

How many mph do fast trains and record cars reach?

Speeds of trains in passenger service and records for trains and production cars, in km/h and in mph.
VehicleSpeed in km/hSpeed in mph
TGV Duplex, E5 and ICE 3 in France in passenger service320 km/h198.84 mph
CR400 Fuxing in passenger service in China350 km/h217.48 mph
Shanghai Maglev in passenger service431 km/h267.81 mph
SSC Tuatara, recognized production car record, 2021455.3 km/h282.91 mph
Bugatti Chiron Super Sport 300+, one-way run, 2019490.484 km/h304.77 mph
Yangwang U9 Xtreme, one-way run, September 20, 2025496.22 km/h308.34 mph
TGV, record on steel rails, April 3, 2007574.8 km/h357.16 mph
SCMaglev L0, rail speed record, April 21, 2015603 km/h374.69 mph
The train speeds come from the list of rail speed records[7]. A production car record is the average of two runs in opposite directions. The Bugatti and the Yangwang ran in one direction only, so the record list names the SSC Tuatara as the record holder[8].

Which number formats does this converter accept?

The field reads every one of these formats and converts it, so there is nothing to tidy up before you paste. The table shows what the converter does with each entry, and the converter worked out every result itself.
What you typeWhat the converter showsHow we read it
10062.1371 mphA number on its own is read as kilometres per hour, because that is the unit on the field.
100 km/h62.1371 mphThe km/h symbol pasted with the number is skipped, because the field already works in kilometres per hour.
100 kph62.1371 mphThe abbreviations kph and kmph stand for the same unit, so the field skips them as well.
80.550.0204 mphThe decimal point separates the fraction, exactly as you would expect.
80,550.0204 mphA comma followed by one or two digits can only be a decimal comma, so the result is the same.
1,500932.0568 mphA comma before three digits groups thousands in English, so this is fifteen hundred kilometres per hour. A note under the field shows the other possible reading, 1.5.
1.5000.9321 mphA single point is always read as a decimal point, so the field counts one and a half kilometres per hour. A note under the field shows the other possible reading, 1500.
1 500932.0568 mphA space between the thousands, as written in much of Europe and in SI style, gives the same result as 1,500.
60 mph60 mphMiles per hour are converted to kilometres per hour, with a line under the field saying so, so the result comes back to 60 mph.

How do you read a km/h limit on an mph speedometer?

Four steps turn the number on a metric sign into the point you look for on a dial marked in miles per hour.

  1. Type the number from the sign

    In the Kilometers per hour field, type the limit from the sign, for example 90.

  2. Read the result in mph

    The converter shows 55.9234 mph. On a dial marked in miles per hour, look just short of 56.

  3. Copy the result

    The Copy result button puts the number on your clipboard, so you can keep a note of the limits along your route.

  4. Open the reverse conversion when you know the speed in mph

    The Swap order button opens the mph to km/h converter and carries the result from this page over to it. There you type the value from the dial and see it in km/h straight away.

Sources

  1. Kilometres per hour — Wikipedia
  2. Miles per hour — Wikipedia
  3. Mile — Wikipedia
  4. Speed limits — Gouvernement du Québec
  5. Speed limits in Ireland — Wikipedia
  6. Metrication in Canada — Wikipedia
  7. Land speed record for rail vehicles — Wikipedia
  8. Production car speed record — Wikipedia
  9. The Road Vehicles (Construction and Use) Regulations 1986, regulation 35 — legislation.gov.uk
  10. Speedometer — Wikipedia
  11. Knot (unit) — Wikipedia

Every figure in the tables was computed from the unit definitions and checked arithmetically before publication. Historical values and the names of local units come from the sources listed above.

Content last reviewed: · written and checked by the Arteon team

Common questions about converting km/h to mph

Is 100 km/h the same as 60 mph?

100 km/h is 62.14 mph. In the other direction, 60 mph is 96.56 km/h. The gap between the two speeds is 3.44 km/h. In miles per hour that is 2.14 mph.

Why does a UK car show km/h on the speedometer as well?

A vehicle first used on or after 1 April 1984 must have a speedometer capable of showing speed in both miles per hour and kilometres per hour[9]. On a dial like that you read a metric limit directly. An older car may show mph only, and then the converter does the sum. UK limits converted to km/h are listed on the page of the mph to km/h converter.

Does a speedometer show the exact speed?

A speedometer approved under UN ECE Regulation 39 may not show less than the actual speed[10]. In the approval test the upper limit of the reading is 110% of the actual speed plus 4 km/h. At 80 km/h a speedometer may therefore show up to 92 km/h. In miles per hour that is 57 mph[10].

When did Canada switch its speed limits to km/h?

Every speed limit sign in Canada was changed from mph to km/h over the Labour Day weekend in 1977[6]. From the same time every new car sold in Canada had to show speed in km/h. Canadian railways still give their speed limits in miles per hour[6].

What treadmill speed in mph matches a pace of 6 minutes per kilometer?

A pace of 6 minutes per kilometer is 10 km/h, because you cover ten such kilometers in an hour. Converted, that is 6.21 mph. On a treadmill set to miles per hour you choose 6.2.

Is a mile per hour the same as a knot?

A knot is one nautical mile per hour and equals exactly 1.852 km/h[11]. One knot is 1.15078 mph. Knots are used in meteorology and in maritime and air navigation[11].

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