Distance, Time & Speed Calculator
Solve distance, elapsed time or average speed with independent metric and US units. Convert the result into common speeds without mixing units.
Calculate an average speed, a journey duration or a distance from the other two quantities. Each input has its own unit, so a distance in miles and a time in minutes can produce kilometres per hour directly. The conversion table shows several equivalent speeds for checking a result against a map, schedule or instrument.
How to use this tool
- Choose the quantity to calculate.
- Enter the other two values; the field for the answer is ignored.
- Select the unit beside each quantity, including the desired answer unit.
- Read the main result and compare its equivalent speeds in the table.
Formula
speed = distance ÷ time; time = distance ÷ speed; distance = speed × time
The calculation first expresses distance in metres and time in seconds. A mile is exactly 1,609.344 m and a nautical mile is exactly 1,852 m. The selected answer unit is applied after solving the equation.
Example
Covering 10 km in 20 minutes gives 10 ÷ (20/60) = 30 km/h, or about 8.333333 m/s. At a constant 30 mph, covering 60 miles takes 2 hours. Include any planned stops separately if the quoted speed is a moving speed.
Frequently asked questions
Is average speed the mean of two speeds?
Not usually. Divide total distance by total elapsed time. Two equal-distance legs at different speeds take different times, so their simple arithmetic mean is misleading.
Does this predict an arrival time?
It returns a duration from the supplied distance and speed. Traffic, route selection, acceleration and departure time are not modelled.
Can the answer be zero?
Zero distance over positive time gives zero average speed. Solving for time requires positive speed; a stationary object cannot provide a finite travel-time estimate for a positive distance.
Is this velocity?
It uses path distance, not signed displacement. It therefore calculates speed without a direction.
Sources
Last updated: 2026-10-30