Speed, Distance & Time Calculator
Enter two of speed, distance and time to find the third. Time can be entered in hours, minutes and seconds.
Formulas
- Speed = distance ÷ time
- Distance = speed × time
- Time = distance ÷ speed
Distances can be in m, km, miles or feet, and speeds in km/h, m/s, miles per hour or knots. The calculator uses these definitions and exact fractions: 1 mile = 1,609.344 m, 1 foot = 0.3048 m, and 1 knot = 1,852 m per hour. A value that does not divide evenly is labeled "rounded value".
Examples
| You want | You enter | Result |
|---|---|---|
| Speed | 120 km in 2 hours | 60 km/h |
| Distance | 60 km/h for 90 minutes | 90 km |
| Time | 10 km at 4 km/h | 2.5 hours (2 hours 30 minutes) |
When you enter 0
| Input | Result |
|---|---|
| Distance 0, time greater than 0 → speed | 0 |
| Distance greater than 0, time 0 → speed | Not available (you cannot divide by 0) |
| Distance 0, time 0 → speed | Not available (the value is not determined) |
| Speed 0 → distance | 0 |
| Distance greater than 0, speed 0 → time | Not available (you never arrive) |
| Distance 0, speed 0 → time | Not available (the value is not determined) |
| Distance 0, speed greater than 0 → time | 0 |
How this differs from other calculators
- The Speed Converter changes the unit of a speed, such as km/h to m/s. This calculator finds one of speed, distance and time from the other two.
- The Running Pace Calculator is built for race distances (half marathon, marathon and so on), pace per km or mile, and split times. This calculator is general: it works for cars, walking, boats or anything else that moves at a steady speed.
Notes
- The average speed is total distance ÷ total time. If your speed changes, averaging the speeds gives a different answer. For example, driving a route at 60 km/h and returning at 40 km/h gives an average of 48 km/h for the round trip, not 50 km/h.
- Acceleration, multiple legs combined and relative speed are not covered. Time must be under 1,000 hours.
- Time is entered in three boxes: hours, minutes and seconds (empty boxes count as 0). Minutes are 0–59, and seconds are 0 or more and less than 60 (up to 3 decimal places).
- To convert a length of time on its own, use the Time Converter.
- Use a period as the decimal separator; commas are accepted only as thousands separators (1,234.5).
- The definitions of the mile, foot and knot used here are the same ones as in the Speed Converter, which cites NIST SP 811 as its source (checked on October 31, 2026).
Frequently asked questions
How do I find speed from distance and time?
Choose "Speed", then enter the distance and the time. 120 km in 2 hours gives 60 km/h.
How do I find the average speed of a round trip?
Divide the total distance of the round trip by the total time. Do not average the two speeds.
What if the trip takes more than a day?
You can enter more than 24 in the hours box (for example, 36 hours), up to under 1,000 hours in total.