Data, Health & Finance

Pace & Speed Calculator

Work out any one of pace, speed, distance or time from the other two — for running, walking or cycling. Enter a distance and a finish time to get your pace and speed, or combine a target pace with a distance or time to find the rest. Distances can be in kilometres, miles or metres, and the calculator lays out split times so you can see the cumulative clock at each kilometre or mile. Pace and speed are reciprocals: a 5:00 min/km pace is exactly 12 km/h.

How to use this tool

  1. Choose what to solve for: pace & speed, time, or distance.
  2. Enter the two values you know — distance and time, or pace with distance/time.
  3. Pick your distance unit (km, miles or metres) and the pace unit.
  4. Read pace, speed, time and distance together, plus the split times.
  5. Times are entered as M:SS or H:MM:SS; pace as M:SS per km or mile.

The formula

Pace, speed, distance and time are linked by one relationship: distance equals speed times time. Pace is the inverse of speed — time taken per unit distance — which is why runners think in minutes per kilometre rather than kilometres per hour.

speed = distance ÷ time pace = time ÷ distance (= 1 ÷ speed) split_time = pace × split_distance
pace
Time per unit distance, e.g. 5:00 /km
speed
Distance per unit time, e.g. 12 km/h

A 5:00 min/km pace is exactly 12 km/h. Halving your pace time doubles your speed, since the two are reciprocals.

Worked examples

10 km run

Given
10 km in 50:00
Result
5:00 /km, 12 km/h

Speed = 10,000 m ÷ 3000 s = 3.33 m/s = 12 km/h; pace = 1000 ÷ 3.33 = 5:00 per km.

Marathon target

Given
5:00 /km pace, 42.195 km
Result
≈ 3:30:59

At 5:00 per km, 42.195 km takes about 3 hours 31 minutes.

Cycling

Given
40 km in 1:20:00
Result
30 km/h

40 km in 80 minutes is exactly 30 km/h, or a 2:00 per km pace.

Frequently asked questions

They are reciprocals. Speed is distance per time (km/h); pace is time per distance (minutes per km). Runners prefer pace because it answers "how long will each kilometre take", while speed suits cycling and driving. A 5:00 min/km pace equals exactly 12 km/h.

Times use M:SS or H:MM:SS — so 50:00 is fifty minutes and 3:30:00 is three and a half hours. Pace uses M:SS per kilometre or mile, like 5:00. You can also enter plain seconds. The calculator parses all of these.

From your pace, held even, the calculator multiplies pace by each split distance to give the cumulative clock time at 1 km, 2 km, and so on (or per mile). It assumes a constant pace, so use them as a target rather than a prediction of exactly how an effort will unfold.

Yes. The maths is identical for any steady-paced activity — walking, running or cycling. Just enter the relevant distance and time or pace. Cyclists usually think in km/h or mph, which the tool shows alongside pace.

Even splits are an idealisation. In reality, hills, wind, fatigue, drafting and pacing strategy all shift your pace kilometre to kilometre. Negative splits (speeding up) or fading are common. Use the even-split table as a plan to aim at, then compare it against what you actually run or ride.