🏃Running & Endurance
Calculators for runners and endurance athletes: pace and splits, race-time prediction, VO2 max, heart-rate training zones, and calories burned.
Getting started
Plan and pace your next race
New to the running tools? Use them in this order to go from a recent result to a race-day plan.
- Race Time PredictorSet a realistic goal time from a recent race result.This target becomes the anchor every other number in your plan is built from.
- Training Pace CalculatorTurn that goal into your easy, threshold and interval training paces.Training at the right paces is what actually makes the goal time achievable.
- Race Fueling CalculatorBuild a carbohydrate, fluid and sodium plan for race day.Fuelling stops you fading late, so you can hold the pace you trained for.
- Marathon Pace CalculatorLock in your goal pace and 5K split targets for the race.Turns the whole plan into concrete numbers to hit on the day.
All running & endurance calculators
Pace Calculator
Enter any two of distance, time, and pace — get the third instantly, plus per-km and per-mile splits.
Race Time Predictor
Enter a recent race result and target distance to estimate your finish time using the proven Riegel formula.
VO2 Max Calculator
Estimate your VO2 max from a race distance and time using the Daniels–Gilbert model.
Calories Burned Running
Estimate how many calories you burn on a run based on your weight, pace, and duration.
Heart Rate Zone Calculator
Find your five personal heart-rate training zones using your age (or measured max HR) and resting heart rate.
Pace Converter
Convert any running speed or pace into all four common units — min/km, min/mile, km/h and mph.
Treadmill Pace Converter
Turn a treadmill speed and incline into the equivalent outdoor running pace, accounting for the effort the incline adds.
Marathon Pace Calculator
Enter a goal marathon finish time to get the pace you need to hold, your halfway target, and cumulative splits.
Half Marathon Pace Calculator
Enter a goal half marathon finish time to get your required pace, halfway split, and cumulative split targets.
Run Walk Calculator
Plan a run/walk strategy: set your run and walk intervals and paces to see your blended pace and estimated finish time.
Training Pace Calculator
Enter a recent race result to get personalised easy, tempo, threshold, interval and rep training paces.
Negative Split Calculator
Plan a negative split by choosing how much faster to run the second half of your race.
Max Heart Rate Calculator
Estimate your maximum heart rate from your age using several validated formulas side by side.
Running Cadence Calculator
Enter any two of cadence, stride length and speed to solve for the third.
Steps to Distance Calculator
Convert a step count into distance in kilometres and miles, estimated from your height and stride.
Running Weight Loss Calculator
Estimate how many runs it takes to reach a fat-loss goal from running alone, based on your weight and typical run.
Calories Burned Walking
Estimate how many calories you burn walking based on your weight, speed and duration.
Sweat Rate Calculator
Work out how much you sweat per hour so you can plan hydration for training and racing.
Race Fueling Calculator
Plan your carbohydrate, fluid and sodium intake for a long race based on your expected duration.