Whether you just finished a parkrun or you are planning your first half marathon, pace is the number that ties everything together. Enter a distance and finish time to get your pace per mile and per kilometer, your average speed, and predicted times for the most popular race distances.

Running Pace Calculator

How Pace Is Calculated

Pace is simply your total time divided by distance. A 5K in 27:00 is 27 minutes divided by 3.11 miles, or about 8:41 per mile. Speed is the same idea flipped around: distance divided by time, shown here in miles per hour.

How Race Predictions Work

The race time predictions use the Riegel formula: T2 = T1 x (D2 / D1) ^ 1.06. The 1.06 exponent reflects the fact that runners slow down slightly as distance goes up. It works best when you predict from a recent, all-out race and when you have trained properly for the target distance. Predictions from a 5K to a marathon are often optimistic for newer runners who have not built up their long runs.

Goal Pace per Mile Pace per Kilometer
30:00 5K 9:39 6:00
25:00 5K 8:03 5:00
1:00:00 10K 9:39 6:00
2:00:00 Half Marathon 9:09 5:41
4:00:00 Marathon 9:09 5:41
3:30:00 Marathon 8:01 4:59

Training by Pace vs. Heart Rate

Pace tells you how fast you are going, while heart rate tells you how hard your body is working to go that fast. On hot days, hills, or tired legs, the same pace costs more effort. Many runners use pace targets for races and intervals, and heart rate targets for easy days. Our Heart Rate Zone Calculator helps you set those easy-day limits, and the VO2 Max Calculator gives you a sense of your current aerobic ceiling.

Getting Accurate Pace From a GPS Watch

  • Wait for a full GPS lock before you start, especially in a new location.
  • Use dual-frequency or multi-band GPS if your watch supports it, particularly in cities and under trees.
  • Use lap pace or average pace rather than instant pace, which jumps around.
  • For treadmill runs, calibrate the watch after a few outdoor runs or use a foot pod.

Disclaimer: Race predictions are estimates and assume appropriate training for each distance. It is not medical advice. Talk with a healthcare provider before making major changes to your exercise, diet, or sleep, especially if you have a health condition or take medication.