Speed Distance Time Calculator

Calculate speed, distance, or time given the other two values.

Enter your values

Results

Enter your values and press Calculate.

Why use this calculator

The speed-distance-time relationship is one of the most fundamental concepts in physics and everyday life, from planning road trips to understanding athletic performance.

How to use it

Select what you want to solve for, then enter the two known values. For speed: enter distance and time. For distance: enter speed and time. For time: enter distance and speed.

The formula

Speed = Distance / Time. Distance = Speed × Time. Time = Distance / Speed.

Worked examples

  • 100 miles in 2 hours

    Speed = 50 mph

  • 60 mph for 3.5 hours

    Distance = 210 miles

When people use it

  • Road trip planning
  • Running pace calculations
  • Physics homework
  • Travel time estimation

Tips

  • Ensure units are consistent (miles with hours, or km with hours)
  • Average speed accounts for stops and speed changes

Questions people ask

How do I convert mph to km/h?
Multiply mph by 1.60934. For example, 60 mph = 96.56 km/h.