What does VDOT stand for?

VDOT is a shorthand for V-dot-O2max, written as V̇O₂max in scientific notation. It represents a performance-derived index of aerobic capacity developed by Jack Daniels.

Is VDOT the same as VO2max?

No. VO2max is a laboratory-measured physiological ceiling. VDOT is a performance-based index that accounts for both aerobic capacity and running economy, making it more useful for training prescription.

How accurate is VDOT for predicting race times?

VDOT predictions are most accurate when your anchor race is recent (within 4-8 weeks), you are well-trained for the target distance, and conditions are similar. Predictions become less reliable as the distance gap between anchor and target increases.

How often should I recalculate my VDOT?

Recalculate after each race or hard time trial. For ongoing training, recalculating every 4-6 weeks during a build phase keeps your training paces current with your fitness.

Can I use a 5K VDOT to predict marathon time?

You can generate a prediction, but it assumes marathon-specific training. A 5K-based VDOT overestimates marathon potential if you lack the long-run volume and fueling practice needed for the full distance.

What Is VDOT? How Runners Use It for Training Paces and Race Planning

VDOT is not VO2max

VO2max is a lab measurement of your body's maximum oxygen consumption. VDOT is different: it is a performance-derived number that accounts for both your aerobic capacity and your running economy. Two runners can have identical VO2max values but different VDOT scores because one uses oxygen more efficiently at race pace.

This distinction matters because training prescription based on lab VO2max alone misses the economy factor. VDOT captures both, making it a more practical anchor for setting training intensities.

VO2max

Laboratory measurement of maximum oxygen uptake. Requires gas analysis equipment. Reflects physiological ceiling but not running-specific efficiency.

VDOT

Performance-derived index from Jack Daniels. Calculated from race results. Reflects both aerobic capacity and running economy in one number.

How VDOT is calculated

The VDOT calculation uses two components from Jack Daniels' validated model:

Step 1: Oxygen cost

VO2 = -4.60 + 0.182258v + 0.000104v²

Where v is your velocity in meters per minute. This estimates the oxygen cost of running at your race pace.

Step 2: Percent VO2max utilization

%VO2max = 0.8 + 0.1894e^(-0.01278t) + 0.2989e^(-0.1933t)

Where t is race duration in minutes. Shorter races use a higher percentage of VO2max than longer ones.

Result: VDOT

VDOT = VO2 / %VO2max

Your VDOT score. Higher values indicate better race fitness. Typical recreational runners fall in the 30-50 range; competitive club runners 50-60; elite runners 65-85.

VDOT reference table

This table shows equivalent race times at selected VDOT values. If your VDOT is between two rows, your expected times fall between those rows as well.

VDOT	5K	10K	Half Marathon	Marathon
30	33:00	1:08:42	2:33:15	5:20:42
35	29:30	1:01:23	2:16:02	4:44:31
40	26:49	55:51	2:03:53	4:16:37
45	23:50	49:35	1:49:22	3:47:14
50	21:26	44:36	1:37:14	3:23:37
55	19:26	40:25	1:27:12	3:04:17
60	17:42	36:47	1:18:48	2:48:12
65	16:12	33:40	1:12:01	2:34:40
70	14:53	30:55	1:06:12	2:23:04
75	13:43	28:31	1:01:06	2:13:01

Source: Daniels' Running Formula (3rd edition). Values are approximate and assume flat, neutral conditions.

What VDOT tells you about training

The practical value of VDOT is that it generates training paces. Daniels defined five training zones, each serving a specific physiological purpose:

Easy pace (E)

59-74% of VO2max velocity. The foundation of training volume. Develops aerobic base, promotes recovery, and builds durability for harder sessions.

Marathon pace (M)

75-84% of VO2max velocity. Race-specific work for marathon training. Also useful for long tempo segments in half marathon preparation.

Threshold pace (T)

83-88% of VO2max velocity. Improves lactate clearance and the ability to sustain faster paces for longer. Typically 20-minute tempo runs or cruise intervals.

Interval pace (I)

97-100% of VO2max velocity. Targets VO2max improvement. Typical sessions: 800m-1200m repeats with equal recovery.

Repetition pace (R)

Faster than VO2max velocity. Develops speed and running economy. Short repeats (200m-400m) with full recovery.

When to recalculate VDOT

Your VDOT is only as current as your last anchor race. Recalculate when:

You run a new race or time trial
Your training suggests a fitness shift (positive or negative)
You start a new training block and need updated paces
More than 6-8 weeks have passed since your last anchor

Limitations of VDOT

Predictions assume you are equally trained for all distances. A 5K specialist will not automatically hit VDOT-predicted marathon times.
Weather, terrain, altitude, and course profile affect race outcomes but are not reflected in the base VDOT model.
VDOT does not account for fueling, hydration, or pacing execution errors during a race.
It is a model, not a guarantee. Use it as a planning anchor and validate against real training response.

Calculate your VDOT

Enter a recent race result and get your VDOT score, training paces, and race predictions.

VDOT Calculator Running Performance Calculator Training Zones Calculator

Related guides

VO2max Explained

What VO2max measures, how it differs from VDOT, and why it matters for runners.

Training Zones Calculator

Calculate your pace and heart rate zones from VDOT and heart rate data.

What Is VDOT? How Runners Use It for Training Paces and Race Planning

VDOT is not VO2max

VO2max

VDOT

How VDOT is calculated

VDOT reference table

What VDOT tells you about training

Easy pace (E)

Marathon pace (M)

Threshold pace (T)

Interval pace (I)

Repetition pace (R)

When to recalculate VDOT

Limitations of VDOT

Calculate your VDOT

Related guides

Editorial references

Apply this guide with a matching tool

Related guides