Use these calculators to work out your running pace, predict a finish time from a pace, convert between miles and kilometers, and see what an even-pace goal means at other race distances.
Pace calculator
Distance converter
Race pace table
How the calculations work
Pace is total time divided by distance. A mile is exactly 1.609344 kilometers, a half marathon is 21.0975 km (13.1094 miles) and a marathon is 42.195 km (26.2188 miles). Results are rounded to the nearest second.
The race pace table shows the time you would run at exactly the same pace over other distances. It is a pacing reference, not a race prediction: most runners slow down as distance increases, so a 4:00:00 marathon pace held over 5K is not the same as your 5K race potential.
Use these numbers as a guide
These tools do arithmetic only. They do not account for terrain, heat, fitness or health, and they are not training or medical advice. Build mileage gradually, and talk to a doctor before starting or stepping up training if you have a health condition or have not exercised in a while.
Related guides: Marathon training, Half marathon, Race day preparation.