Running Pace Calculator

Pace = time ÷ distance. Speed = distance ÷ time. Each split projects that pace across a standard race distance (finish time = pace per km × distance in km).

Constant-pace projection; 1 mile = 1.609344 km.

Assumes an even effort. Real races drift — most runners slow in the second half — so longer projected splits read slightly optimistic.

Interval or variable-pace sessions, where an average pace hides the structure of the workout.

Pace is simply time divided by distance. Run 5 km in 25 minutes and your pace is 5:00 per kilometre (or about 8:03 per mile). The calculator does the division and converts between km and miles for you.

Pace is time per unit distance (minutes per km or mile) — lower is faster. Speed is distance per unit time (km/h or mph) — higher is faster. Runners usually think in pace; treadmills and cyclists usually show speed. We display both.

Splits are your projected finish times at each standard race distance if you held the same pace throughout. They're useful for pacing: glance at the 5K or 10K split to check you're on schedule during a longer race.

Even pacing — or a slight negative split, where the second half is a touch faster — is the most efficient way to race. Going out too fast is the most common pacing mistake and usually costs more time later than it gains early.

One mile is 1.609 km, so your per-mile pace is always slower (a larger number) than your per-km pace. The calculator shows both at once so you don't have to do the arithmetic on race morning.