This calculator uses the fundamental physics formula: Speed = Distance ÷ Time. It accepts any two values (speed, distance, or time) and solves for the third. Speed is always normalized to mph internally using conversion factors, then displayed in your selected unit. Time is entered as hours, minutes, and seconds for easy input and rendered the same way.
GPS and navigation apps account for real-world factors: stops at lights, turns, acceleration/deceleration, traffic, and actual road distances. This calculator assumes constant speed with no interruptions on a straight line.
Yes. If you run 5 miles in 40 minutes, enter distance as 5 mi and time as 0h 40m 0s. The speed will show your pace. For pace in minutes per mile, use the dedicated Pace calculator which formats the output differently.
Miles per hour (mph) and kilometers per hour (km/h) measure the same thing at different scales. 1 mile equals approximately 1.609 kilometers, so 60 mph is about 96.5 km/h.
Subtract stop time from your travel time. If the full trip is 4 hours but includes 30 minutes of stops, enter 3.5 hours (or 3h 30m) as the time to calculate average moving speed.
No. This is pure kinematics math. Air resistance and altitude do not change the basic relationship between speed, distance, and time. Real-world speed (like climbing a hill) may be affected, but the formula stays the same.
This calculator assumes constant speed. In reality, vehicles accelerate at the start and decelerate at the end. The average speed will be lower than the peak speed if acceleration/deceleration time is significant.
Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.