Running pace calculator
Enter any two of distance, time and pace to get the third, in minutes per mile or per kilometer. See mile or kilometer splits, and predict your time at other distances from a recent race.
- Distance
- 3.11 mi · 5 km
- Time
- 0:25:00
- Pace per mile
- 8:03 /mi
- Pace per kilometer
- 5:00 /km
- Speed
- 7.5 mph · 12.0 km/h
Pace = time ÷ distance; speed = distance ÷ time. 1 mile = 1.609344 km.
Mile splits at an even pace
| Mile | Split | Elapsed |
|---|---|---|
| 1 | 8:03 | 0:08:03 |
| 2 | 8:03 | 0:16:06 |
| 3 | 8:03 | 0:24:08 |
| Final 0.11 mi | 0:52 | 0:25:00 |
Every full mile takes the same time at an even pace; elapsed is your running time at the end of each.
Splits assume the same pace the whole way. Hills, wind and heat change real splits. Not medical advice: if you’re new to running or have a health condition, check with your doctor before hard efforts.
- Free, no sign-up
- Works on phone and desktop
How to work out your running pace
- 1
Choose what to work out: pace, finish time, distance, or a race prediction.
- 2
Pick miles or kilometers, then a race distance or your own custom distance.
- 3
Type the time in hours, minutes and seconds, or the pace per mile or kilometer.
- 4
Read the answer, with pace in both units, speed and a splits table you can use on race day.
Features
Pace, time or distance
Enter any two and get the third, in minutes per mile and per kilometer, plus mph and km/h.
Splits for race day
Mile or kilometer splits with your running time at each marker, including the final partial split.
Race predictor
Turn a recent race into likely times from the mile to the marathon, with an honest note on accuracy.
Private
Everything is worked out on your device. Nothing is sent anywhere, and there’s nothing to sign up for.
How pace, time and distance fit together
Pace, time and distance are linked by one simple relationship, so any two give you the third:
- Pace = time ÷ distance (minutes per mile or per kilometer)
- Time = distance × pace
- Distance = time ÷ pace
- Speed = distance ÷ time (mph or km/h), which is 60 ÷ pace in minutes
The calculator converts miles and kilometers exactly (1 mile = 1.609344 km) and rounds to the nearest second only at the end, so a marathon time doesn’t pick up rounding errors from every mile.
Worked examples
- Pace from a 5K: 25:00 for 5 km is 5:00 per kilometer, or 8:03 per mile, a speed of 7.5 mph.
- Finish time from a pace: a marathon at 9:00 per mile takes 26.2188 × 9 minutes = 3:55:58. Note the extra two-tenths of a mile: it adds almost two minutes.
- Distance from a time: an hour at 10:00 per mile covers 6 miles (9.66 km).
Finish times at common paces
| Per mile | 5K | 10K | Half | Marathon |
|---|---|---|---|---|
| 7:00 | 0:21:45 | 0:43:30 | 1:31:46 | 3:03:32 |
| 8:00 | 0:24:51 | 0:49:43 | 1:44:53 | 3:29:45 |
| 9:00 | 0:27:58 | 0:55:55 | 1:57:59 | 3:55:58 |
| 10:00 | 0:31:04 | 1:02:08 | 2:11:06 | 4:22:11 |
| 11:00 | 0:34:11 | 1:08:21 | 2:24:12 | 4:48:24 |
| 12:00 | 0:37:17 | 1:14:34 | 2:37:19 | 5:14:38 |
Each extra minute per mile adds about 3 minutes to a 5K and about 26 minutes to a marathon.
The race predictor
The predictor uses the formula the engineer Peter Riegel published in American Scientist in 1981, after studying world records across endurance sports: T2 = T1 × (D2 ÷ D1)1.06. T1 and D1 are the time and distance of your race, D2 the distance you want to predict. The exponent of 1.06 means each doubling of distance takes a little more than twice as long, because you can’t hold the same pace for longer.
Example: a 10K in 50:00 predicts a half marathon in 1:50:19 (8:25 per mile) and a marathon in 3:50:01. Predicting the marathon from that half marathon time gives the same answer, 3:50:01: the formula is consistent whichever race you start from.
Where it’s less reliable: a 2016 study of 2,303 recreational runners found Riegel’s formula well calibrated up to the half marathon, but its marathon predictions were too fast, by at least 10 minutes for half of the runners. For the runner above, a marathon of 4:00 or slower would be no surprise. Predictions also assume you have trained for the new distance and run it in similar conditions, and they work best from a recent, all-out race rather than a training run.
What the numbers can’t tell you
A calculator assumes an even pace on a flat course. Hills, heat, wind, altitude and crowded starts all slow real races, and a pace you can hold in training isn’t always one you can hold for a whole race. Use the result as a plan, then adjust on the day. If you’re new to running or returning after a long break, build up gradually.
To train by effort rather than pace, find your zones with the heart rate zone calculator. For fueling, the TDEE calculator estimates how many calories you burn in a day, and the macro calculator and protein calculator help split them up. Recovery matters too: plan bedtimes with the sleep calculator, or track body composition with the body fat calculator.
Sources
- Riegel PS. Athletic records and human endurance. American Scientist, 1981.
- Vickers AJ, Vertosick EA. An empirical study of race times in recreational endurance runners. BMC Sports Science, Medicine and Rehabilitation, 2016.
These are estimates for planning, not medical advice. If you have a heart condition or other health concern, or are pregnant, talk to your doctor before training hard or racing.
Frequently asked questions
How do I calculate my running pace?
Divide your time by the distance. A 5K in 25 minutes is 25 ÷ 5 = 5 minutes per kilometer. A 5K is 3.11 miles, so the same run is 25 ÷ 3.107 = 8:03 per mile.
How do I convert pace per mile to pace per kilometer?
A mile is 1.609344 kilometers, so divide a pace per mile by 1.609344 to get the pace per kilometer, or multiply the other way. For example, 9:00 per mile is 5:36 per kilometer, and 5:00 per kilometer is 8:03 per mile.
How accurate is the race time predictor?
For most runners it’s a reasonable guide up to the half marathon. In a 2016 study of 2,303 recreational runners, Riegel’s formula predicted times well up to that distance, but its marathon predictions were too fast, by at least 10 minutes for half of the runners. Treat a predicted marathon time as a best case unless you’ve trained specifically for the distance.
What’s the difference between pace and speed?
Pace is time per distance (minutes per mile); speed is distance per time (miles per hour). They are two views of the same thing: 10:00 per mile is 6 mph, and 5:00 per kilometer is 12 km/h. Runners use pace because it maps straight onto mile markers and a watch.
How long is a half marathon and a marathon?
A marathon is 42.195 km (26.22 miles) and a half marathon is exactly half that, 21.0975 km (13.11 miles). In the calculator, both presets use these exact distances, so a marathon in miles ends with a final 0.22-mile split.
How do I use the splits table in a race?
Pick two or three markers, such as miles 3, 6 and 10, and note the elapsed time the table gives for each. During the race, compare your watch with those times to see whether you’re ahead of or behind your target, and by how much.
Can I use this for walking or cycling?
Yes. Pace and time are simple arithmetic, so they work for any activity at a steady speed, from about 30 seconds to an hour per kilometer. The race predictor is the exception: it’s meant for running races.
More free tools
- TDEE CalculatorYour maintenance calories.
- Calorie Deficit CalculatorDaily calories and a goal date.
- Macro CalculatorProtein, carbs and fat in grams.
- BMI CalculatorBody mass index for adults.
- Body Fat CalculatorBody fat from a tape measure.
- Heart Rate ZonesTraining zones, including zone 2.
- Sleep CalculatorBedtimes that fit sleep cycles.
- Due Date CalculatorDue date and weeks pregnant.
- Ovulation CalculatorFertile window and ovulation date.
- Dog Age CalculatorDog years to human years.