Free running tools
Train smarter, not just harder.
Fast, no-signup calculators for runners: pace, race-time prediction, heart-rate zones, VO₂ max and calories. Built for your 5K, 10K, half and full marathon goals, in kilometres or miles.
Pace Calculator
Find your pace and speed from any distance and time. Switch km/miles.
Race Time Predictor
Predict your 5K, 10K, half or marathon time from a recent result.
Calories Burned
Estimate calories burned running, based on your weight and effort.
VO₂ Max
Estimate your aerobic fitness from a 12-min test or heart rate.
Heart Rate Zones
Get your 5 training zones in bpm from age or max heart rate.
Steps to Distance
Convert steps to km and miles, plus calories walking or running.
Which calculator do I need?
“What pace do I need for my goal time?”
Enter the race distance and your target time in the Pace Calculator. It gives the pace per km or mile to hold from start to finish. Open it →
“What could I run in a longer race?”
Put a recent race into the Race Time Predictor. It uses the Riegel formula, the standard used by most coaches, to project 5K, 10K, half and marathon times. Open it →
“How hard should my easy runs be?”
Heart Rate Zones turns your age or max heart rate into five training zones in bpm, so easy days stay easy and hard days count. Open it →
“How fit am I, really?”
The VO₂ Max calculator estimates your aerobic capacity from a 12-minute run or your resting and max heart rate. Open it →
Running guides
Short answers to the questions runners actually search for, each one paired with the calculator that puts the numbers to work.
Pace & speed
Race times
Calories
Walking & steps
About these tools
Every calculator runs in your browser: nothing to install, no account, and your numbers never leave your device. The formulas are the ones coaches and sports scientists use (Riegel for race prediction, Karvonen and max-heart-rate methods for zones, MET values for calories, the Cooper test for VO₂ max), and each page explains how its result is worked out so you can judge it for yourself.
Running a club or coaching site? You can add the pace calculator to your own website for free.