What time formats can I use?

Enter times as hh:mm:ss or mm:ss (for example 1:45:30 or 50:00) and paces as mm:ss per km or mile (for example 5:00). The calculator parses both automatically.

Can it predict a marathon or 10K finish time?

Yes — choose the time mode, enter the race distance and your target pace, and it returns the finish time. For pace, enter a distance and a time and it returns your pace per km or mile plus average speed.

Is any of this sent to a server?

No. All pace, time and distance calculations run entirely in your browser and nothing is uploaded.

Running Pace Calculator

Work out pace, finish time or distance for any run.

Running pace calculator

Three calculations in one: find your pace per kilometre or mile from a distance and time, predict a finish time from a distance and target pace, or work out distance from a time and pace. Pace mode also shows your average speed in km/h and mph.

Pick what to calculate, enter your numbers in mm:ss or hh:mm:ss, and the answer updates instantly — all in your browser, nothing uploaded.