About Pace Calculator
Pace Calculator is a free tool for runners that connects the three numbers every runner cares about — pace, time, and distance — and adds the things you usually need next: race splits, a pace chart, equivalent race-time predictions, training paces, and unit and treadmill conversions. Enter any two values and it works out the third instantly, in miles or kilometers.
Why we built it
Most pace calculators are cluttered, slow, or buried in ads, and many don’t work well on a phone or remember to convert between miles and kilometers. We wanted one clean page that loads fast, works on any device, runs entirely in your browser (so it keeps working offline once loaded), and doesn’t ask you to create an account. No sign-up, no app, no paywall.
How the numbers are calculated
The core calculator is simple arithmetic: pace is time divided by distance, and the tool rearranges that relationship to solve for whichever value you leave blank. The more advanced features use widely used endurance-running models:
- Equivalent race times use the Riegel formula (T₂ = T₁ × (D₂ ÷ D₁)1.06), a well-known way to estimate performance across distances.
- Splits are derived from your goal time, with options for even, negative, or positive pacing.
- Training, heat, and elevation estimates are based on common coaching guidance and are clearly labelled as estimates — they’re a starting point, not a prescription.
A note on accuracy
The basic pace, time, and distance maths are exact. The predictions are models: useful for setting realistic goals, but they can’t account for your individual training, the course, or the weather on race day. Always treat them as a guide and listen to your body. For the full picture, see our Privacy Policy and Terms & Conditions.
Get in touch
Found a bug, or have an idea for a feature? We’d genuinely like to hear it — email gazalafarheen023@gmail.com.