A speed converter changes a rate. This speed converter uses meters per second as the base. Kilometers per hour are 1000 m / 3600 s. Miles per hour use the international mile of 1609.344 m in an hour. A knot is one nautical mile (1852 m) per hour. Feet per second use the international foot of 0.3048 m. Those factors are exact on this page. A knot is not “about a mile per hour.”
The page converts a scalar speed. Negative values are rejected. It will not apply wind, current, or pace per kilometer. It will not convert a duration; that belongs on the Time Duration Calculator, which is not a timezone tool either.
Length units appear here only as part of the rate. To convert 5 km to miles without a time, use the Length Converter.
Empty and non-numeric input fail. Zero is allowed. Enter converts. Labels sit above the field.
100 km/h to mph is 100 × 1000 / 1609.344, about 62.1371192237 mph. 1 m/s is 3.6 km/h. 1 knot is 1.852 km/h. 60 mph is 88 ft/s exactly on these factors (60 × 1609.344 / 3600 / 0.3048 = 88).
100 km/h = 62.1371192237 mph
1 m/s = 3.6 km/h
1 kn = 1.852 km/hWrite km/h or mph next to the number. A dashboard that says “60” without a unit is not a converted speed.
Road signs switch between km/h and mph at borders. The conversion is the same arithmetic as Example: multiply or divide by 1000/1609.344. Aviation and marine notes use knots because they share the nautical mile with charts. Putting a knot speed into an mph box without converting is how an ETA is wrong by about fifteen percent.
Meters per second are the SI rate and the usual science note. Feet per second show up in ballistics and some US engineering notes. This page will not convert pace (min/km) or a gear ratio. If you have a distance and a duration, divide them yourself, then convert the rate here.
Wind reported in knots and a car reported in km/h are still speeds. Convert one number at a time. Adding them in mixed units is not this tool’s job. Running pace, cadence, and airspeed indicators with compressibility corrections are also out of scope. Type the indicated number you already have and pick the unit printed next to it. Zero speed is allowed. A blank field after swap is still empty and still an error. Very large values above 1e15 are refused so the result cannot become Infinity. Scientific notation is accepted when it is a real number. Commas in thousands are stripped before the convert. Keyboard users can press Enter from the field or either list.
A knot is one nautical mile (1852 m) per hour. Miles per hour use the international mile (1609.344 m).
No. A knot is 1852 m per hour. A mile per hour is 1609.344 m per hour.
Multiply by 1000/1609.344. 100 km/h is about 62.137 mph.
No. Use the Length Converter when there is no time.
This page converts a scalar speed, not a signed velocity.