Speed, Distance & Time Calculator
Enter any two of speed, distance and time and get the third — with results in miles, kilometres and metres.
Reviewed by the WorldCalcs team · Methodology · Last reviewed: July 2026
Speed
50.00 km/h
mph
31.07
m/s
13.89
What is a speed, distance and time calculator?
Speed, distance, and time are locked together by one simple relationship, so if you know any two of them you can always find the third. This calculator does exactly that: fill in two boxes, pick your units, and it solves for the missing one — whether you are planning a drive, pacing a run, or checking an average speed.
The formulas
All three come from the same equation, rearranged:
- Speed = Distance ÷ Time
- Distance = Speed × Time
- Time = Distance ÷ Speed
You can mix units freely — miles with minutes, kilometres with hours — because the calculator converts everything to a common base before doing the math, then reports speed in miles per hour, kilometres per hour, and metres per second at once.
Example
A 100 km trip that takes 2 hours is a speed of 100 ÷ 2 = 50 km/h, which is about 31.07 mph. Driving at 60 mph for 3 hours covers 60 × 3 = 180 miles, or 289.68 km. Running 26.2 miles at 8 mph takes 26.2 ÷ 8 = 3.275 hours — that is 3 hours, 16 minutes, and 30 seconds.
Related: convert between speed units in the Speed Converter, pace a run with the Running Pace Calculator, plan a trip with the Fuel Cost Calculator, or switch length units with the Length Converter.
All calculations happen in your browser. Nothing is sent, stored, or tracked.
Results are estimates and may contain errors — for general information only, not professional advice. Always verify before relying on them. Disclaimer
How to use
Pick which value you want the calculator to solve for, then enter the other two. Choose your units for each field — the math is done in a common base internally.
Speed answers appear in mph, km/h and m/s; distance in miles, km and metres; time as both a decimal and h min s.