Speed Converter
Fixpio’s speed converter restates a speed in the unit you actually think in — instantly, in your browser. Enter a value, pick the unit you have and the unit you need, and the answer updates as you type: a speed limit in kilometres per hour on a trip abroad, a boat or wind speed given in knots, or a running pace you want in miles per hour. Same speed, same journey — just a number you can picture.
Convert Speed
Enter a speed and choose your units — the result appears straight away.
Road limits are posted in mph in the US and UK, and in km/h in most other countries. Check which unit a sign or speedometer uses before comparing numbers.
One converter for the road, the water and the track
The speeds people convert most, in the units they actually meet.
Travel and driving limits
Hiring a car abroad swaps every sign into km/h while your instincts stay in mph. Knowing that 50 km/h in town is 31.07 mph — and that a 120 km/h motorway limit is 74.56 mph — makes the new signs readable from the first junction.
Boats, planes and weather
Wind and vessel speeds arrive in knots whether you sail or not. Twenty knots is a brisk 23.02 mph; converting a forecast before a crossing or a flight turns an unfamiliar unit into a decision you can make.
Running and cycling pace
Training apps and race reports mix km/h, mph and metres per second. A steady 12 km/h run is 7.46 mph; a 25 km/h cycle is 15.53 mph. Converting puts your pace next to the event, treadmill or training plan written in the other system.
About this converter
Most visits to a speed converter start with a limit or a reading in the wrong unit: mph to km/h for a road trip, km/h to mph for a rental car, knots for anything on water. The maths behind every result on this page is the same — the speed is first expressed in metres per second, then converted into the unit you chose, using the exact relationship that 1 mile per hour equals 1.609344 kilometres per hour. That is why the familiar benchmarks land where they do: the UK motorway limit of 70 mph is 112.65 km/h, and a 100 km/h limit abroad is 62.14 mph.
The other units on this page anchor just as firmly. One knot is one nautical mile per hour — exactly 1.852 km/h, or 1.15078 mph — and it is the standard unit for ships, aircraft and marine weather worldwide. Metres per second, the scientific unit, converts to km/h by multiplying by 3.6 (so 10 m/s is 36 km/h), and feet per second, used in US engineering and ballistics, converts at 1 ft/s = 0.3048 m/s — which is why 88 ft/s is exactly 60 mph. Whichever pair you choose, the speed itself does not change; only the way it is described does.
Frequently asked questions
Straight answers about mph, km/h, knots and metres per second.
How many km/h is 60 mph?
60 mph × 1.609344 = 96.5606 km/h, so about 96.56 km/h. To convert any mph figure to km/h, multiply by 1.609344; for a quick mental estimate, multiplying by 1.6 is close enough to judge a speed limit, but use the full factor — or the converter above — when the exact figure matters.
How fast is 100 km/h in mph?
100 km/h × 0.621371 = 62.14 mph. It is one of the most useful benchmarks to remember, because 100 km/h is a standard highway limit in many countries — in mph terms it sits just above the familiar 60 mph mark, not far below a 65 mph US interstate limit (104.61 km/h).
What is the difference between mph and km/h?
Both measure the same thing — distance travelled in one hour — but over different distances: miles in the US and UK, kilometres in most of the rest of the world. Because a mile is longer than a kilometre, the same speed always gives a smaller number in mph than in km/h. A sign reading “50” therefore means something very different in each system: 50 mph is 80.47 km/h, while 50 km/h is only 31.07 mph.
What is a knot?
A knot is one nautical mile per hour. A nautical mile is exactly 1,852 metres — slightly longer than a land mile — so 1 knot equals exactly 1.852 km/h, about 1.15078 mph and 0.514444 m/s. Knots are the standard speed unit for ships and aircraft worldwide, and marine weather forecasts use them too, because the nautical mile ties directly to latitude on a chart. Say “20 knots”, not “20 knots per hour” — the “per hour” is already built in.
How do I convert between m/s and km/h?
Multiply metres per second by 3.6 to get km/h, and divide km/h by 3.6 to get m/s. So 25 m/s is 90 km/h, and 90 km/h is 25 m/s. The 3.6 comes from the clock and the ruler together: 3,600 seconds in an hour, divided by 1,000 metres in a kilometre.
I run at 12 km/h. How fast is that in mph and m/s?
In mph: 12 × 0.621371 = 7.46 mph. In metres per second: 12 ÷ 3.6 = 3.33 m/s. That is a steady training pace — about a 30-minute 10K pace is faster, at roughly 20 km/h (12.43 mph), while a brisk walk sits near 5 km/h (3.11 mph). Converting your usual pace once makes treadmill settings and race targets in the other system easy to read.