VDOT Calculator
A 50:00 10K gives a VDOT of 40.0, which is equivalent to a 1:50:52 half marathon and a 3:49:34 marathon, with threshold runs at 8:12 per mile (5:05 per km).
Enter any recent race to estimate your running fitness with the Daniels and Gilbert equations. This works as a VO2 max calculator for runners, but it is an estimate from a race, not a lab-measured VO2 max.
VDOT
40.0
From
10K in 50:00
5K24:06
Half1:50:52
Marathon3:49:34
A 10K in 50:00 gives a VDOT of 40.0.
What training paces does your VDOT give?
Five paces, each set as a share of your VDOT. Most of your running should be easy; for the default result that is 9:25 to 10:49 per mile. Hard sessions use threshold, interval or repetition pace, and marathon pace is the VDOT's predicted marathon speed.
Easy and long
Most of your running. Conversational, builds the aerobic base.
62-74% of VDOT
9:25-10:49/mi5:51-6:43/kmMarathon pace
Steady sections inside long runs. Teaches race rhythm.
Predicted marathon pace
8:45/mi5:26/kmThreshold
Comfortably hard, about one hour race effort. Raises the pace you can hold.
About 88% of VDOT
8:12/mi5:05/kmInterval
Hard 3 to 5 minute reps. Builds VO2 max.
About 97.5% of VDOT
7:33/mi4:41/kmRepetition
Short fast reps with full recovery. Economy and speed.
About 6 s per 400 m faster than interval
7:09/mi4:26/km
What race times is your VDOT equivalent to?
The same VDOT predicts a time at every distance. The table also shows Riegel's formula beside it as a second opinion. Both are estimates and both assume you have trained for the distance.
Pace unit
| Distance | Riegel | VDOT |
|---|---|---|
| Mile | 7:137:13/mi | 7:077:07/mi |
| 5K | 23:597:43/mi | 24:067:45/mi |
| 10Kyour result | 50:008:03/mi | 50:008:03/mi |
| Half marathon | 1:50:198:25/mi | 1:50:528:27/mi |
| Marathon | 3:50:018:46/mi | 3:49:348:45/mi |
Estimates, not promises. Both assume you have trained for the longer distance.
How is VDOT calculated?
Daniels and Gilbert fitted two equations to measurements of trained runners, published in Oxygen Power: Performance Tables for Distance Runners (1979). The first gives the oxygen cost of running at speed v in metres per minute. The second gives the share of VO2 max a runner can hold for a race lasting t minutes. VDOT is the first divided by the second:
VO2(v) = −4.60 + 0.182258 v + 0.000104 v²
%max(t) = 0.8 + 0.1894393 e^(−0.012778 t) + 0.2989558 e^(−0.1932605 t)
VDOT = VO2(v) ÷ %max(t)
With your result substituted in:
t = 50:00 = 50.00 min · v = 10000 m ÷ 50.00 min = 200.0 m/min
VO2 = −4.60 + 0.182258 × 200.0 + 0.000104 × 200.0² = 36.01 ml/kg/min
%max = 0.8 + 0.1894393 × e^(−0.012778 × 50.00) + 0.2989558 × e^(−0.1932605 × 50.00) = 0.9000
VDOT = 36.01 ÷ 0.9000 = 40.0
VDOT 40.0
Training paces run the first equation backwards: threshold pace is the speed whose oxygen cost is 88% of your VDOT, interval pace 97.5%, and easy running 62% to 74%. The methodology page lists every constant.
Is VDOT the same as VO2 max?
No. VO2 max is the most oxygen your body can use, measured in a lab by breathing into a mask on a treadmill. VDOT is a performance number: the VO2 max a runner of average economy would need to run your race time. Two runners with the same lab VO2 max can have different VDOTs, because the more economical one runs faster on the same oxygen.
That is why VDOT is more useful for training than a lab figure or a watch estimate: it comes from what you actually ran. It is still an estimate. A bad day, a hilly course or heat will lower it, and it can only be as good as the race you enter.
VDOT table: race times for each VDOT
Equivalent times computed from the same equations, for quick reference. Each distance links to its pace chart.
Frequently asked questions
What is VDOT?
VDOT is Jack Daniels' single number for running fitness, worked out from a race result with the oxygen-cost and time-to-exhaustion equations he published with Jimmy Gilbert in 1979. A 50:00 10K gives a VDOT of 40.0. It sets training paces and predicts equivalent race times.
Is this a VO2 max calculator?
It is the closest honest version of one for runners. VDOT is sometimes called effective VO2 max because it is in the same units (ml/kg/min), but it is estimated from how fast you raced, so it folds in running economy and pacing. A lab test measures oxygen uptake directly, and the two numbers often differ by several points.
What VDOT is a 20 minute 5K?
49.8. Enter 5K and 20:00 in the calculator to see the matching training paces and the equivalent times at other distances.
What VDOT do I need for a 4 hour marathon?
About 37.9. That is the VDOT a 4:00:00 marathon itself implies; the half marathon equivalent is 1:56:06. The 4 hour marathon pace chart has the splits.
Which race should I enter?
A recent race you ran all-out on a measured course, ideally 5K to half marathon and within the last six weeks. Parkruns and track races work well. A training run or a hilly or hot race will understate your fitness.
How often should I update my VDOT?
After each race you run all-out. Without a race, Daniels' guideline is to raise training paces by about one VDOT point after four to six weeks of steady training, as long as the current paces feel controlled.