How to use the Pace Calculator
- Pick a race distance or enter a custom one.
- Enter your finish time.
- Read your pace, speed and predicted times for other distances.
Predicting other race times
Race predictions use Riegel’s formula, T2 = T1 × (D2 ÷ D1)1.06, which allows for slowing down over longer distances. It assumes you train for the longer race, so predictions for a marathon from a 5K are optimistic for most runners.
Also searched as: running pace calculator, marathon pace calculator, min per km, min per mile, race time predictor, 5k pace.
Tools that pair well with the Pace Calculator
- Online Stopwatch — A precise stopwatch in your browser: start, record laps, see your fastest and slowest lap, and export the lap times.
- Calorie Calculator — Estimate how many calories you burn per day — your BMR at rest and TDEE with activity — and the daily calories to lose, maintain or gain weight.
- Water Intake Calculator — Estimate how much water to drink each day from your weight, how active you are and how hot it is — shown in liters, ounces and glasses.
- Unit Converter — Convert between metric, imperial and technical units in ten categories — with a two-way converter and a table of every unit at once.
Frequently asked questions
How do I convert min/km to min/mile?
Multiply minutes per kilometer by 1.609. A 5:00 min/km pace is about 8:03 min/mile.
What is a good 5K time?
For recreational runners, 25–35 minutes is typical; under 20 minutes is fast.
Is anything I enter saved or sent?
No. The calculation runs in your browser. Your last inputs are remembered on this device only, so the page opens where you left off.
Can I install Pace Calculator as a web app and use it offline?
Yes. Pace Calculator is an installable web app (PWA) — installed from your browser, not downloaded from an app store. Click Install app at the top of this page in Chrome or Edge (Windows, macOS, Linux, ChromeOS) or on Android, use Share → Add to Home Screen on iPhone and iPad, or File → Add to Dock in Safari 17+ on a Mac. It then opens in its own window with its own icon, and because it runs entirely in your browser it keeps working offline. Firefox on desktop can’t install web apps. How installing works.