How to Use
Select what you want to solve for (Speed, Distance, or Time), enter values for the other two fields in your preferred units, and click Calculate. The result is shown along with common unit conversions.
Frequently Asked Questions
Speed = Distance / Time. The three related formulas are: Speed = Distance / Time, Distance = Speed x Time, Time = Distance / Speed. Enter any two values and this calculator solves for the third.
Multiply mph by 1.60934. For example, 60 mph = 60 x 1.60934 = 96.56 km/h. This calculator handles unit conversions automatically when you select different units.
Average speed = Total Distance / Total Time. If you drove 300 miles in 5 hours, your average speed was 300 / 5 = 60 mph. Note that average speed may differ from typical speedometer readings if you stopped during the trip.
The speed of sound in dry air at 20°C (68°F) is approximately 343 meters per second, 1,235 km/h, or 767 mph. This is often called Mach 1. The speed of light is about 299,792 km/s, roughly 874,000 times faster than sound.
Pace is the inverse of speed, typically expressed as minutes per mile or minutes per kilometer for running. Pace (min/mile) = 60 / Speed (mph). For example, 6 mph = 60 / 6 = 10 minutes per mile.
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