Enter any two of speed, distance and time to solve for the third. Switch units freely, enter time as hours or hh:mm:ss, and use pace mode for running splits in min/km and min/mile.
e.g. 150 or 10
Decimal hours (2.5) or hh:mm:ss / mm:ss (1:30:00, 50:00)
Motion problems always rest on one relationship: distance equals speed times time. Rearrange that identity and you can solve for whichever quantity is missing. This calculator keeps metres and seconds under the hood so mixed units (kilometres with mph, nautical miles with knots) stay consistent, then converts the answer back into the unit you chose plus the common alternatives.
speed = distance ÷ time distance = speed × time time = distance ÷ speed pace (min/km) = (time in minutes) ÷ (distance in km) pace (min/mile) = (time in minutes) ÷ (distance in miles)
Speed = 150 ÷ 2.5 = 60 km/h. That is also 37.2823 mph and 16.6667 m/s.
Time = 1.5 h. Distance = 60 × 1.5 = 90 miles.
Time = 10 ÷ 12 = 0.833… h = 0:50:00 (50 minutes).
5:00 min/km and about 8:03 min/mile.
Distance options include metres, kilometres, statute miles, feet and nautical miles. Speed covers m/s, km/h, mph, knots and ft/s. A statute mile is 1609.344 m; a nautical mile is 1852 m. Converting through metres and seconds avoids rounding drift when you hop between road, running and marine units.
Related tools: Average Speed Calculator · Speed Converter · Time Duration Calculator.
Mixing minutes with hours is the classic error: 90 minutes is 1.5 hours, not 90 hours. Prefer hh:mm:ss when in doubt. Another trap is treating average speed as the mean of two speedometer readings — if the legs cover different distances or times, you must weight by total distance and total time instead.
The three linked formulas are speed = distance ÷ time, distance = speed × time, and time = distance ÷ speed. Enter any two values (with units) and this calculator solves for the third, then shows conversions such as km/h, mph and m/s.
Yes. Use formats like 1:30:00 or 50:00, or enter a decimal number of hours such as 2.5. Results show both H:MM:SS and a readable “h m s” breakdown.
Pace mode is for runners and walkers: given distance and time, it reports minutes per kilometre and minutes per mile (for example 5:00 min/km and 8:03 min/mile for 10 km in 50 minutes).
Average speed adds several journey segments (total distance ÷ total time). This tool solves a single trip for speed, distance or time with unit choices and optional running pace. Use both when you need multi-leg averages plus unit-aware solving.
Distance: m, km, mi, ft, nmi. Speed: m/s, km/h, mph, knots, ft/s. Time: decimal hours or hh:mm:ss. Every result also lists the other common units so you can cross-check without a separate converter.
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