How it works
VDOT = VO₂(v) ÷ %VO₂max(t)
Two regressions from Daniels and Gilbert do the work. One prices the oxygen demand of a running velocity v in meters per minute: VO₂(v) = −4.60 + 0.182258·v + 0.000104·v². The other estimates what share of aerobic capacity a runner can hold for a race lasting t minutes: %VO₂max(t) = 0.8 + 0.1894393·e^(−0.012778·t) + 0.2989558·e^(−0.1932605·t) — short races run near the ceiling, long ones well under it. Your VDOT is the first quantity divided by the second. Equivalent times then fall out by asking, for each distance, what finish would yield that same VDOT — which is exactly how Daniels’ printed tables were generated. Distances and durations are held in meters and seconds internally, so flipping the unit toggle never changes the score.
Sources
- Daniels & Gilbert — the VDOT model Jack Daniels & Jimmy Gilbert, “Oxygen Power: Performance Tables for Distance Runners” (1979). The VO₂-cost and %VO₂max regressions used here are from this work.
- Daniels’ Running Formula Jack Daniels, “Daniels’ Running Formula,” 4th ed. (Human Kinetics, 2021) — VDOT tables, training paces and the equivalent-performance method.
- VO₂max background VDOT is an effort-based stand-in for laboratory VO₂max: it ranks race performances, not a measured oxygen uptake.
FAQ
What does the VDOT number actually measure?
Race performance expressed on a VO₂ max-like scale. Because it comes from what you ran rather than lab gas exchange, it quietly bundles running economy and endurance into the score — which is exactly why coaches trust it for pace-setting even though it is not a direct physiological reading.
How recent and how hard should the race be?
Within the last couple of months, and a genuine race effort — not a tempo run wearing a bib. A soft effort reads as low fitness and every downstream number inherits the error. The model is calibrated from 1.5 km through the marathon, and 5K-to-half results usually score most reliably.
Are the equivalent times promises?
No — they are what your engine is worth if you also do the distance-specific preparation. A strong 5K proves the aerobic fitness behind a marathon equivalent, not the fueling or the durability it demands. For side-by-side predictions from several models, run the same race through a dedicated race-time predictor.
Why is my score lower than my watch’s VO₂ max estimate?
Different evidence. Wrist estimates lean on heart rate versus pace during ordinary training, while VDOT believes only finished races. If you rarely race flat-out, the watch may flatter you — or your racing may genuinely lag your training fitness. Daniels’ paces are calibrated to the race-based number.
How do I turn the score into training paces?
Every VDOT maps to an easy range plus marathon, threshold, interval, and repetition paces in Daniels’ tables. This page keeps the focus on the score and its equivalent finishes; when you are ready to schedule workouts, convert the same race into a full pace chart.
Will racing more often raise my VDOT?
Racing supplies fresher data; training supplies fitness. Expect the score to move across blocks of weeks, not from one weekend to the next. Re-enter each new personal best and watch the equivalents shift together — that consistency is the point of a single-score system.
VDOT scores and equivalent finishes are outputs of a published regression, not measurements of your body and not start-line guarantees. Course, weather, fueling, and preparation decide real results — read everything here as general training information rather than medical or coaching direction.