About Runwise
Runwise is a free set of running calculators — pace, heart rate zones, VO2 max, training paces, race prediction, parkrun prediction, power zones, and workout suggestions — built by runners who got tired of spreadsheets, half-remembered formulas, and calculators that bury a real answer under a login wall.
There's no account to create and nothing is tracked beyond anonymous, aggregate usage stats. Every number Runwise shows you comes from a published, citable method rather than a guess, and every tool explains that method on its own page so you can see exactly how your result was calculated.
We'd rather be the calculator you bookmark and come back to for years than one you use once and forget, which means getting the numbers right matters more to us than anything else about the site.
The methodology behind the numbers
Pete Riegel's endurance-running formula predicts a finish time at one distance from a real result at another, and powers the Race Time Predictor and Parkrun Predictor.
Jack Daniels' VDOT method turns a recent race result into training paces and a VO2 max estimate matched to your current fitness, rather than generic paces based on age or experience. It underpins the Training Paces, VO2 Max, and Workout Suggestions calculators.
ACSM normative VO2 max data, published by the American College of Sports Medicine across age and gender brackets, places a VO2 max estimate into a fitness category on the VO2 Max calculator.
WMA/Alan Jones age-factor tables adjust a parkrun time for age and gender, so runners of different ages can compare performances fairly on the Parkrun Predictor's rating.
Get in touch
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