VDOT is a single fitness number from Jack Daniels' running formula. It is derived from a VO2max model: a faster race performance produces a higher VDOT, and equal VDOTs across distances represent equivalent fitness.

How is VDOT calculated here?

It uses the Daniels–Gilbert equations: VO2 = -4.60 + 0.182258·v + 0.000104·v², where v is velocity in metres per minute, divided by the percentage of VO2max sustainable for the race duration.

Is my race data uploaded?

No — the calculation runs entirely in your browser and nothing leaves your device.

VDOT Running Calculator

Find your VDOT fitness score from any race time (Daniels–Gilbert model).

VDOT running calculator

VDOT is Jack Daniels’ single-number fitness score, built on the Daniels–Gilbert VO2max model. Enter any race result from 1500 m to the marathon and get the VDOT that performance represents.

Because equal VDOTs across distances reflect equivalent fitness, coaches use the number to set training paces and to compare a 5K against a half marathon. The whole calculation happens locally in your browser.