Runners think in pace — minutes per kilometer — because it's what you actually hold during a race. This calculator converts a distance and finish time into pace per kilometer and average speed, the two numbers behind every training plan and race goal.
How it works
Enter the distance and your time in hours, minutes, and seconds. The calculator converts the time to seconds, divides by distance for the pace, and inverts it for speed in km/h.
The formula
Pace is shown as min:sec per kilometer; speed in kilometers per hour. The two are reciprocals: a 5:00/km pace equals exactly 12 km/h.
Worked example
Running 10 km in 55 minutes: pace = 3,300 s ÷ 10 = 330 s = 5:30 per kilometer, or about 10.9 km/h average speed.
Frequently asked questions
How do I predict my time at another distance?
Pace doesn't hold constant across distances. A common tool is Riegel's rule: T₂ = T₁ × (D₂/D₁)^1.06 — a 55-minute 10K predicts roughly a 2:01 half marathon, noticeably slower per km.
What pace do common race goals require?
A sub-30 5K needs 6:00/km, a sub-60 10K also 6:00/km, a sub-2:00 half marathon about 5:41/km, and a sub-4:00 marathon about 5:41/km as well.
Should easy runs be at race pace?
No — most training plans put the bulk of mileage 60–90 seconds per km slower than race pace, reserving faster paces for specific interval and tempo sessions.