Enter a reference pace above to see training zones.
Training zone calculator
This calculator uses Jack Daniels' VDOT formula, a widely used method in exercise science for estimating running fitness from a single race or time-trial result. Enter a recent 5K or 10K time, and the calculator estimates your VDOT score, then derives five training zones (Jog/Easy, Zone 2, Tempo, Threshold, VO2max) as pace ranges, heart-rate ranges, and lap splits.
Training zones exist because different paces stress your body differently. Running everything at one pace — usually too fast — is one of the most common mistakes recreational runners make. Structuring training across zones, with mostly easy running and a few focused hard sessions, builds aerobic fitness while limiting injury risk.
VDOT is a fitness metric developed by exercise physiologist Jack Daniels. It converts a race performance into a single number that predicts equivalent performances at other distances and prescribes training paces.
The zones are estimates based on a validated formula, not a lab test. They're accurate enough to guide day-to-day training, but factors like heat, terrain, and fatigue will shift your actual effort on any given run.
Yes — the calculator needs a real, honest effort (a 5K or 10K time trial or race result from the last few weeks) to estimate your current fitness accurately. Old or non-maximal efforts will skew your zones.
Heart-rate ranges are optional. Leave Max HR and Resting HR blank and the calculator will still show pace-based and lap-split zones.
Yes — fill in the optional Target Race section with a goal distance and time to see your target zones compared side-by-side with your current zones, including how much faster or slower the goal pace is.