Pace Calculator

10 km in 50:00 gives a pace of 5:00 per km (8:03 per mile) and a speed of 12 km/h.

How it works

• Converted the distance to kilometres and the time to seconds.
• Divided the total time by the distance for the pace per kilometre.
• Multiplied the pace by 1.609344 for the pace per mile, and divided the distance by the time for the speed.

pace = time / distance = 3000 s / 10 km = 5:00 per km

• Pace is the inverse of speed: minutes per kilometre, not kilometres per hour.
• Assumes a steady even pace; real races include hills, wind and fatigue.

Methodology

1. Convert the distance to kilometres using the exact mile definition (1 mi = 1.609344 km).
2. Convert the time to seconds and divide by the distance for the pace per kilometre.
3. Multiply the pace by 1.609344 for the pace per mile, and divide the distance by the time for the speed.
4. Round pace to whole seconds and speed to three decimals.

Usage

1. Enter the distance and choose kilometres, miles or metres.
2. Enter the time as hours, minutes and seconds.
3. Read the pace per kilometre and per mile and the average speed.

Examples

These are examples, not current values: they use fixed inputs, while the interactive tool computes live results in your browser.

10 km in 50 minutes

{
  "distance": 10,
  "distanceUnit": "km",
  "hours": 0,
  "minutes": 50,
  "seconds": 0
}

Half marathon (21.0975 km) in 1:45

{
  "distance": 21.0975,
  "distanceUnit": "km",
  "hours": 1,
  "minutes": 45,
  "seconds": 0
}

5 miles in 40 minutes

{
  "distance": 5,
  "distanceUnit": "mi",
  "hours": 0,
  "minutes": 40,
  "seconds": 0
}

Limitations

Distance and time

Pace is simply the total time divided by the distance, so it is a rate calculation; the same run has one pace and one speed. The mile is defined internationally as exactly 1.609344 km, so mile and kilometre paces convert exactly before rounding.