Running Pace Calculator

Updated 2026-09-09

Enter a distance and a finish time to get your pace per kilometre and per mile, or enter a distance and a goal pace to get the finish time. The calculator also gives your speed, an even-pace split table, and Riegel equivalent race times for the 5K, 10K, half marathon, and marathon.

How Running Pace Works

Pace is simply time divided by distance, reported as minutes and seconds per kilometre or per mile. It is the number that makes training portable: a target pace tells you exactly how hard to run whether you are on a track, a treadmill, or a trail, and it is how race goals are set and split. Enter any two of distance, time, and pace above and the calculator fills in the rest, then converts between kilometres and miles so you never have to.

Speed is the same information the other way round. A pace of 5:00 per kilometre is 12.0 km/h, or about 7.5 mph. Treadmills use speed, most races and watches use pace, so the result card shows both.

Even Splits and Race Predictions

The split table assumes you hold an even pace the whole way, which is the reference every pacing plan starts from. Run the early kilometres a touch slower and the closing ones a touch faster, a negative split, and you will finish at or ahead of the even-pace time. Start faster than it and you will almost always fade; going out too hard is the single most common pacing mistake.

The equivalent race times come from Riegel's formula (Riegel, 1981): T2 = T1 x (D2 / D1)^1.06. A 25-minute 5K predicts roughly a 52-minute 10K and a 1:56 half marathon. The prediction assumes you have trained for the longer distance; the marathon in particular needs its own long-run base, and without it real times come in slower than the formula suggests. Treat the predictions as a target that your training has to earn.

Making the Pace Faster

A pace calculator tells you where you are; raising your ceiling is what moves it. The two levers are a bigger aerobic engine and a higher fraction of it you can hold. Easy mileage in zone 2 builds the engine, and hard intervals raise its size: four-minute efforts at 90 to 95% of max heart rate, the Norwegian 4x4, raised VO2 max 7.2% in eight weeks in a controlled trial (Helgerud et al., 2007). Tempo runs at threshold lift the pace you can sustain. The full playbook is in how to run faster.

Frequently Asked Questions

How do I calculate running pace?

Pace is time divided by distance. Divide your finish time in seconds by the distance, then convert back to minutes and seconds: 25 minutes for 5 km is 1500 divided by 5, which is 300 seconds, or 5:00 per kilometre. The calculator above does this and also gives pace per mile and speed.

What is a good 5K pace?

For recreational runners, 25 to 30 minutes (5:00 to 6:00 per kilometre) is a solid benchmark. Beginners often finish in 30 to 40 minutes; competitive club runners go under 20 minutes, about 4:00 per kilometre. The most useful comparison is your own pace trending down over time.

How do I predict my marathon time from a shorter race?

Use Riegel's formula: predicted time equals your known time times (new distance divided by old distance) to the power 1.06. It assumes you have trained for the longer distance, which for the marathon means dedicated long runs; without that base, real times come in slower. The table above shows Riegel predictions for every standard distance.

How do I convert pace between kilometres and miles?

One mile is 1.609 kilometres, so pace per mile is pace per kilometre times 1.609. A 5:00 per kilometre pace is about 8:03 per mile. The calculator shows both at once, plus speed in km/h and mph.

How do I run a negative split?

Run the second half faster than the first. Use the even-pace splits above as the reference: start a few seconds per kilometre slower, then finish a few seconds faster. Even or slightly negative pacing gives most runners their fastest times.

References

1. Riegel PS. Athletic records and human endurance. American Scientist. 1981;69(3):285-290.
2. Helgerud J, Høydal K, Wang E, et al. Aerobic high-intensity intervals improve VO2max more than moderate training. Med Sci Sports Exerc. 2007;39(4):665-671. PubMed