Running Pace Calculator

What a pace calculator does

Pace is simply how long it takes you to cover one unit of distance — a mile or a kilometre. Distance, time, and pace are locked together by one relationship: pace = time ÷ distance. Give this tool any two of those three numbers and it solves the missing one, then translates your pace into both miles and kilometres so it works no matter which system your watch or race uses.

Why runners plan by pace

Holding an even, repeatable pace is the single most reliable way to hit a goal time without blowing up early. Once you know your target pace, you can check it at every mile marker, dial it into a treadmill, or program it into a GPS watch. The projected 5K, 10K, half marathon, and full marathon times let you see how today's effort would scale up to race day — a quick reality check before you sign up for a distance.

How to use it

1. Pick what you want to Solve for: pace, time, or distance.
2. Fill in the other two boxes — the field you are solving for is greyed out automatically.
3. Enter time as hh:mm:ss (or mm:ss) and pace as mm:ss.
4. Read your pace per mile and per kilometre, plus projected race finish times, updated live as you type.

FAQ

Can I mix miles and kilometres?

Yes. Set the distance and pace units independently. The results always show pace both per mile and per km.

How do I enter a pace like 8 minutes 30 seconds?

Type 8:30 in the pace box and choose "per mile" or "per km" beside it.

Are the race times a prediction?

They assume you hold the exact pace shown for the whole distance. Real races usually slow over longer distances, so treat the marathon estimate as a best case.

Is my data saved?

No. Everything runs in your browser and nothing is sent anywhere or stored.

These results are estimates for training and planning, not professional coaching or medical advice.