Speed Distance Time Calculator
Solve for speed, distance, or time — enter any two values to find the third. Supports km/h, mph, m/s, knots, kilometres, and miles.
All calculations happen in your browser. No data is sent anywhere.
Find Speed
Find Distance
Find Time
The Speed Distance Time Formula
How it works
The three quantities are always linked: Speed = Distance ÷ Time, Distance = Speed × Time, Time = Distance ÷ Speed. If you know any two, you can always find the third. Time is entered in hours, minutes, and seconds and automatically converted for the calculation. Results are shown in the unit you select.
Speed unit reference
- km/h → mph: × 0.621371
- mph → km/h: × 1.60934
- km/h → m/s: ÷ 3.6
- km/h → knots: ÷ 1.852
- km → miles: × 0.621371
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Open converter →FAQ
What is the speed distance time formula?
Speed = Distance ÷ Time. Distance = Speed × Time. Time = Distance ÷ Speed. Knowing any two values lets you calculate the third. This calculator handles all three cases with multiple unit options.
How do I convert km/h to mph?
Multiply km/h by 0.621371 to get mph. To go the other way, multiply mph by 1.60934. Example: 100 km/h × 0.621371 = 62.14 mph. The "Find Speed" tab automatically shows your result in all four speed units.
How do I convert km/h to m/s?
Divide km/h by 3.6 to get m/s. To convert m/s to km/h, multiply by 3.6. Example: 90 km/h ÷ 3.6 = 25 m/s.
What is a knot?
A knot equals one nautical mile per hour, approximately 1.852 km/h or 1.151 mph. Knots are used in maritime and aviation navigation because nautical miles align with the Earth's geometry (1 nautical mile ≈ 1 arcminute of latitude).