Pace Calculator
Solve for pace, time or distance and get split times for common race distances.
Inputs
Enter as HH:MM:SS (e.g. 0:50:00) or MM:SS (e.g. 5:00).
Pace (per km)
05:00
Finish Time
0
Pace (per mile)
08:02
Speed
12.00km/h
Step by step
Total time
= 50:00
Distance
= 10 km
Pace per km
50:00 ÷ 10 km
= 05:00 /km
Race splits at this pace
| Distance | km | Finish Time |
|---|---|---|
| 1 km | 1.000 | 05:00 |
| 5K | 5.000 | 25:00 |
| 10K | 10.000 | 50:00 |
| 15K | 15.000 | 1:15:00 |
| Half Marathon | 21.098 | 1:45:29 |
| Marathon | 42.195 | 3:30:58 |
How it works
Pace, time and distance form a simple triangle of relationships — knowing any two gives you the third. This calculator solves all three directions and extends the result to a split table for common race distances. The split table lets runners verify even-pacing strategy or set milestone targets for marathon training.
Formulas
Pace
Pace = Total Time ÷ Distance
- p
- Pace (seconds per km or mile)
- T
- Total time in seconds
- D
- Distance in km or miles
Finish time
Finish Time = Pace × Distance
Distance
Distance = Total Time ÷ Pace
Pace calculations are mathematical and assume constant effort throughout the distance. Real-world performance varies with terrain, weather, fatigue and pacing strategy. Use finish time predictions as a guide, not a guarantee.
Frequently Asked Questions
What does 'pace' mean in running?
Pace is the time taken to cover one unit of distance (typically one kilometre or one mile). A pace of 5:00 /km means you cover one kilometre every five minutes. It's the inverse of speed — faster running = lower pace number.
How do I run a sub-4-hour marathon?
You need a pace of 5:41 /km (9:09 /mile). Input a 42.195 km distance with a target time of 3:59:59. The calculator will show the required pace and confirm whether it's achievable based on your current training paces.
Should I use km or miles?
Use whichever matches your GPS watch and race. Most road races outside the US use kilometres. The calculator always shows both pace formats — you can use one as a cross-check regardless of which unit you entered.