Running Pace Calculator
Enter a distance and a time to get your pace per km and per mile, your speed, split times, race predictions and training paces.
Type h:mm:ss or mm:ss, like 1:45:00 or 25:30. A plain number means minutes.
Pace as m:ss, like 5:30.
Split times
0 = even pace. 1–3% is a typical negative split. A minus number means a slower second half.
| Split | At | Split time | Total time | Pace |
|---|
Race time predictor
Uses the distance and time above as your recent race.
1.06 is Riegel's standard figure. A bigger number means you slow down more over longer races (try 1.08 if you're newer to long runs).
| Race | Predicted time | Pace per km | Pace per mile |
|---|
Riegel's formula: new time = old time × (new distance ÷ old distance)exponent. It assumes you've trained for the longer race, so treat marathon predictions from short races as a best case.
Training paces (rough guide)
| Run type | Pace per km | Pace per mile |
|---|
A rough guide, not a coaching plan. The bands are simple shares of your current 5K race speed (easy 70–78%, tempo 92–95%, intervals 100–104%, fast reps 105–110%), close to the zones coaches commonly quote. Go by feel on hot, hilly or tired days.
Treadmill speed for your pace
| Belt speed | Pace per km | Pace per mile |
|---|
Incline: with no wind to push against, treadmill running feels a little easier. Many runners set a 1% incline to match outdoor effort.
Track lap times
| Track distance | Time at your pace |
|---|
A standard outdoor track is 400 m in lane 1. Outer lanes are longer, so your lap times there will look slower.
How your pace is worked out
Pace = time ÷ distance. Speed is the same thing flipped over.
- 1
Time in seconds
55:00= 3,300 s
- 2
Distance
10 km= 6.21 mi
- 3
Pace per km
3,300 s ÷ 10= 330 s= 5:30 /km
- 4
Per mile and speed
330 s × 1.609344= 8:51 /mi= 10.91 km/h
Read more: the formula, a worked example, splits, race predictions and training paces
Pace is how long you take to cover one km or one mile. Speed is the same thing flipped over: how far you go in an hour. Runners and walkers usually think in pace; cyclists think in speed. For a general speed, distance and time sum in any units (knots, m/s, swim and row pace), use the speed, distance and time calculator.
The formula
pace = time ÷ distance
time = pace × distance
distance = time ÷ pace
pace per mile = pace per km × 1.609344
speed in km/h = 60 ÷ pace in minutes per km
predicted time = old time × (new distance ÷ old distance)^1.06
Worked example
You run 10 km in 55:00. That's 55 × 60 = 3,300 seconds, so your pace is 3,300 ÷ 10 = 330 seconds per km, or 5:30 per km. Per mile it's 330 × 1.609344 = 531.08 seconds, or 8:51 per mile. Your speed is 60 ÷ 5.5 = 10.91 km/h, which is 10.91 ÷ 1.609344 = 6.78 mph. A 400 m lap at this pace takes 330 × 0.4 = 132 seconds (2:12).
Finish time and distance
- Finish time: a marathon (42.195 km) at 5:00 per km takes 42.195 × 300 = 12,658.5 seconds, about 3:30:59.
- Distance: 30 minutes at 6:00 per mile covers 30 ÷ 6 = 5 miles (8.05 km).
Splits and negative splits
At an even pace every km of the example takes 5:30. With a 2% negative split, the second half takes 2% less time than the first: the first 5 km take 3,300 ÷ 1.98 = 1,666.7 seconds (27:47, 5:33 per km) and the second 5 km take 1,633.3 seconds (27:13, 5:27 per km).
Race predictions
Pete Riegel's formula predicts a time for a new distance from a recent race: new time = old time × (new distance ÷ old distance)1.06. From 55:00 for 10K, a half marathon is 3,300 × 2.109751.06 = 7,281 seconds (2:01:21) and a marathon is 3,300 × 4.21951.06 = 15,181 seconds (4:13:01). A 5K comes out at 26:23.
Training paces
The training table starts from your predicted 5K speed (5,000 m ÷ 1,582.8 s = 3.16 m/s for the example) and takes simple shares of it: easy runs at 70–78% (7:32 to 6:46 per km), tempo at 92–95% (5:44 to 5:33 per km), intervals at 100–104% (5:17 to 5:04 per km) and fast reps at 105–110%. Marathon pace is the Riegel marathon prediction (6:00 per km). Treat these as a rough guide, not a coaching plan.
Common paces
| Per km | Per mile | km/h | 5K | 10K | Marathon |
|---|---|---|---|---|---|
| 4:00 | 6:26 | 15.00 | 20:00 | 40:00 | 2:48:47 |
| 5:00 | 8:03 | 12.00 | 25:00 | 50:00 | 3:30:59 |
| 6:00 | 9:39 | 10.00 | 30:00 | 1:00:00 | 4:13:10 |
| 7:00 | 11:16 | 8.57 | 35:00 | 1:10:00 | 4:55:22 |
| 9:00 | 14:29 | 6.67 | 45:00 | 1:30:00 | 6:19:45 |
Results assume a steady pace on a flat course. Hills, heat, wind and how you feel on the day all change real race times. Riegel's formula and the training bands are rules of thumb, not guarantees.
Common questions
How do I work out my running pace?
Divide your time by your distance. 10 km in 55:00 is 3,300 seconds ÷ 10 = 330 seconds, or 5:30 per km. Multiply by 1.609344 for pace per mile: 8:51 per mile. Your speed is 60 ÷ 5.5 = 10.91 km/h, or 6.78 mph.
How do I convert min per km to min per mile?
Multiply pace per km by 1.609344, because a mile is 1.609344 km. 5:30 per km is 330 × 1.609344 = 531 seconds, or 8:51 per mile. To go the other way, divide pace per mile by 1.609344. The calculator shows both paces on every result.
How do I predict my marathon time from a 10K?
Advanced mode uses Pete Riegel's formula: new time = old time × (new distance ÷ old distance) to the power 1.06. A 55:00 10K predicts a marathon of about 4:13:01, which is 6:00 per km. It assumes you have trained for the longer distance, so treat it as a best case.
What treadmill speed is 5:30 per km?
Speed is 60 ÷ pace in minutes. 5:30 per km is 5.5 minutes, so 60 ÷ 5.5 = 10.91 km/h, or 6.78 mph. Many runners set the treadmill to a 1% incline to make up for the lack of wind resistance indoors. The treadmill table in Advanced lists common belt speeds.
What is a negative split?
Running the second half of a race faster than the first. With a 2% negative split, the second half takes 2% less time than the first. For 10 km in 55:00, the first 5 km take 3,300 ÷ 1.98 = 1,666.7 seconds (27:47) and the second 27:13, about 5:33 then 5:27 per km.
How long is a 400 m lap at my pace?
Multiply your pace per metre by 400. At 5:30 per km, a 400 m lap takes 330 × 0.4 = 132 seconds, or 2:12. A 10 km run is 25 laps of a standard track, measured in lane 1. Outer lanes are longer, so lap times there will look slower.
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