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VDOT calculator

Short answer

VDOT is the VO2 max your race result implies. Daniels and Gilbert's equations estimate the oxygen cost of your race pace and divide it by the share of VO2 max a runner can hold for that long. A 25:00 5K gives a VDOT of 38.3, which matches a 51:53 10K and a 3:57:55 marathon.

Last reviewed 28 October 20261 published sourcesNot medical advice

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VDOT calculator

Use a recent all-out race or time trial between 1,500 m and the marathon.

h
min
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Choose your race distance and enter your time.

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Equivalent race times by VDOT
VDOT5K10KMarathon
3030:411:03:494:49:49
3526:5956:024:16:06
4024:0650:013:49:37
4521:4945:133:28:16
5019:5641:203:10:40
5518:2238:062:55:55
6017:0335:222:43:22
6515:5533:022:32:35
7014:5631:012:23:13
Solved from Daniels and Gilbert's equations. Daniels' printed tables can differ from these by a few seconds.

Daniels and Gilbert's equations

Jack Daniels and Jimmy Gilbert published two equations in Oxygen Power (1979). The oxygen cost of running at v metres per minute is −4.60 + 0.182258v + 0.000104v² mL/kg/min, and the fraction of VO2 max that can be sustained for a race lasting t minutes is 0.8 + 0.1894393e^(−0.012778t) + 0.2989558e^(−0.1932605t). VDOT is the oxygen cost divided by that fraction (Lan et al., 2020).

Researchers still use the same equations: Lan et al. used them to estimate the aerobic capacity of firefighter recruits (Lan et al., 2020). Equivalent times come from solving the equations backwards for each distance.

We took the coefficients from Lan et al.'s 2020 reproduction rather than the out-of-print original. As a check, a 20:00 5K gives a VDOT of 49.8, in line with Daniels' published table, which lists about 19:57 for a VDOT of 50 (Lan et al., 2020).

Related tools

The race time predictor uses Riegel's formula instead, and the pace calculator converts any time into pace per kilometre or mile.

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Common questions

How is VDOT calculated?

The oxygen cost of running at velocity v (metres per minute) is −4.60 + 0.182258v + 0.000104v². The share of VO2 max you can hold for t minutes is 0.8 + 0.1894393e^(−0.012778t) + 0.2989558e^(−0.1932605t). VDOT is the first divided by the second.

Is VDOT the same as VO2 max?

No. It is the VO2 max your performance implies, so it also reflects running economy. Two runners with the same lab VO2 max can have different VDOTs.

How accurate are the equivalent times?

They assume you are equally trained for every distance. Runners with less endurance training often run longer races, especially the marathon, slower than the equivalent time suggests.

Sources

Figures on this page were checked against these publications on 28 October 2026.

  1. Lan FY, Fernandez-Montero A, Yiannakou I, Marinos-Iatrides O, Ankeny JT, Kiser J, et al. A Mediterranean lifestyle is associated with lower hypertension prevalence and better aerobic capacity among New England firefighter recruits. Journal of Occupational and Environmental Medicine. 2020;62(7):466–471. doi.org/10.1097/JOM.0000000000001868

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