Running pace calculator
Enter any two of pace, time and distance and the third is filled in. Everything updates as you type; there is no submit button.
Pace
5:00 /km
5K in 25:00 is 5:00 per kilometre, or 8:03 per mile, which is 12.0 km/h.
Every race distance at this pace
What you would finish in if you held this exact pace the whole way. Over longer distances that is an increasingly big if. The race time predictor accounts for the fact that nobody holds 5K pace for a marathon.
| Distance | Finish time |
|---|---|
| 1500 m | 7:30 |
| Mile | 8:03 |
| 3K | 15:00 |
| 2 miles | 16:06 |
| 5K | 25:00 |
| 8K | 40:00 |
| 5 miles | 40:14 |
| 10K | 50:00 |
| 12K | 1:00:00 |
| 15K | 1:15:00 |
| 10 miles | 1:20:28 |
| 20K | 1:40:00 |
| Half marathon | 1:45:29 |
| 25K | 2:05:00 |
| 30K | 2:30:00 |
| Marathon | 3:30:59 |
| 50K | 4:10:00 |
How pace is calculated
Pace is time divided by distance, and speed is its reciprocal. Everything on this page comes from those two relationships and nothing else. There is no model, no fitting and no assumption:
pace = time / distance— seconds per kilometre or per miletime = pace × distancedistance = time / pacespeed = 3600 / pace— km/h or mph, for a pace in seconds per unit
Distances use the official measured lengths, not the round numbers people say: a half marathon is 21,097.5 m and a marathon is 42,195 m, so a marathon is slightly more than 26.2 miles. A mile is exactly 1,609.344 m by international agreement, which is why kilometre and mile paces never convert to tidy numbers.
Using pace on race day
An even pace is very nearly the fastest way to run any distance from 1500 m upwards, and the most common way runners lose time is going out faster than goal pace in the first kilometre. The metabolic cost of that early surge is repaid with interest later: a rule of thumb from race data is that every second banked in the first mile costs roughly two in the last.
If you want a slight margin, run the first half a touch slower than target and the second half faster. The splits calculator will build that table for you, including the small negative split most coaches recommend.
Kilometres or miles
Use whichever your race is measured in and whichever your watch is set to. Converting mid-race is a good way to make an arithmetic error at the moment you are least able to do arithmetic. The one thing worth knowing by heart is the conversion at your own rough pace: 5:00/km is 8:03/mile, 6:00/km is 9:39/mile, and 4:00/km is 6:26/mile.
Common questions
How do I work out running pace by hand?
Divide your time by your distance. A 25:00 5K is 1500 seconds over 5 kilometres, which is 300 seconds, or 5:00, per kilometre. For miles, divide by 3.107 instead, giving 8:03 per mile. The arithmetic is easy; the reason to use a calculator is to avoid doing it in your head at kilometre 4.
What is a good 5K pace?
There is no single answer, but for context: a 30:00 5K is 6:00/km, a 25:00 5K is 5:00/km, and a 20:00 5K is 4:00/km. Roughly a third of recreational parkrun finishers are under 25 minutes. What matters far more than the absolute number is whether the pace is improving on your own previous times.
Should I train at my race pace?
Mostly no. Around 80% of weekly running for most trained runners is done considerably slower than race pace, because easy running is what builds the aerobic base while leaving you fresh enough to do the hard sessions properly. The VDOT calculator turns a race result into the specific easy, threshold and interval paces that follow from it.
Why does the mile pace not look like the kilometre pace times 1.6?
It does; that is what it is. A mile is 1.609 kilometres, so 5:00/km is 5:00 x 1.609 = 8:03/mile. It surprises people because the two numbers look unrelated at a glance when one is in minutes and seconds.
Does this account for hills, wind or heat?
No. This is straight arithmetic on distance and time. For the effort cost of a gradient, use the treadmill pace converter, which applies a measured cost-of-running curve. Heat and wind have no similarly clean model. As a rough guide, expect to lose noticeable time above about 15 °C, increasing sharply with humidity.