How the pace calculator works
Pace is the time you need per mile or kilometer. It is calculated as time ÷ distance: 50 minutes for a 10K (6.21 miles) gives 8:03 min/mile, or 5:00 min/km. Speed is the inverse — distance per hour — so 8:03 min/mile equals about 7.5 mph (12 km/h). Runners think in pace because race plans, GPS watches and training zones all use it; treadmills and cyclists usually show speed.
Miles and kilometers. Switch units with the km / mi toggle. 1 mile is 1.609 km, so an 8:00 min/mile pace is 4:58 min/km. A half marathon is 13.1 miles (21.0975 km), a marathon 26.2 miles (42.195 km).
Marathon and half marathon pace. A 4-hour marathon — and a 2-hour half marathon — needs 9:09 min/mile (5:41 min/km). A 3:30 marathon or a 1:45 half takes 8:01 min/mile (4:59 min/km), a 5-hour marathon 11:27 min/mile (7:07 min/km). Enter your goal distance and time above to get the exact pace for any other target.
What the level badge means. After you enter a time the calculator sorts your pace into a rough training tier — from couch-to-5K to elite — based on typical adult running paces. It is a playful orientation, not a medical or coaching assessment.
Next steps. Use the same distance and time on the race time predictor to project your finish for other distances, the pace chart to see how a few seconds per mile change your marathon time, or the split calculator to plan even mile splits for race day.