Running Pace Calculator
Get your pace per km and average speed from distance and time, plus projected 5K, 10K, half, and full marathon times at the same pace. Everything runs in your browser.
Enter distance and time
FAQ
Pace vs speed?
Pace is time per km (min:sec/km); speed is distance per hour (km/h). Runners think in pace, cyclists in speed.
How accurate are the projections?
They assume constant pace. Real race pace drops with distance—expect half/full times 5–10% slower than projected.
Can I use miles?
It's km-based—multiply miles by 1.609 first (3 mi = 4.83 km).
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