Speed Distance Time Calculator
Solve for speed, distance, or time given the other two. Step-by-step algebraic working, sport presets, and unit conversions — free and instant.
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Result
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The Speed Distance Time Formula Triangle
How to Calculate Speed, Distance, and Time
The three quantities — speed, distance, and time — are related by one formula: Distance = Speed × Time. Rearrange it to solve for whichever value you need.
Solving for Speed
Divide the distance by the time taken. For example, if a car covers 150 km in 2 hours, its average speed is 150 ÷ 2 = 75 km/h.
Solving for Distance
Multiply speed by time. A cyclist riding at 20 km/h for 3 hours covers 20 × 3 = 60 km.
Solving for Time
Divide the distance by the speed. A 42.195 km marathon at 12 km/h takes 42.195 ÷ 12 ≈ 3 h 31 min.
Unit Conversions
- 1 mile = 1.60934 km
- 1 nautical mile = 1.852 km
- 1 knot = 1 nautical mile per hour = 1.852 km/h
- 1 m/s = 3.6 km/h
Running Pace vs Speed
Runners often express effort as pace (minutes per kilometre or mile) instead of speed. A pace of 5:00 min/km equals 12 km/h. This calculator shows the equivalent pace in its conversions when solving for speed.
Frequently Asked Questions
What is the formula for speed?
Speed = Distance ÷ Time. Ensure distance and time use compatible units — kilometres and hours give km/h, miles and hours give mph.
How do I convert km/h to mph?
Divide by 1.60934. Example: 100 km/h ÷ 1.60934 ≈ 62.1 mph.
What are knots?
A knot is one nautical mile per hour (1.852 km/h), the standard speed unit in aviation and maritime navigation.