How to Use VDOT to Predict Your Race Times
VDOT is the single best predictor of running performance. Learn what it means, how to estimate yours, and how to use it for race predictions and training.
VDOT is a number that represents your current running fitness. Coined by legendary coach Jack Daniels, it's based on your VO2max (maximum oxygen uptake) but adjusted for running economy. A higher VDOT means you're a faster, more efficient runner.
What VDOT numbers mean
VDOT 30 is a beginner runner (about a 30-minute 5K). VDOT 50 is a solid competitive amateur (about a 20-minute 5K or 3:12 marathon). VDOT 70+ is professional/elite territory (about a 14-minute 5K or sub-2:15 marathon).
The beauty of VDOT is that it works across distances. A VDOT of 50 predicts consistent performance whether you're racing a 5K, 10K, half marathon, or marathon.
How to find your VDOT
Run a race. Any recent race result (5K, 10K, half, marathon) gives you your VDOT. Enter your distance and time into the race predictor and it calculates your VDOT automatically using the Daniels formula.
A 5K race is the best test because it's short enough to go all-out but long enough to be aerobically significant. Parkrun is perfect for this.
Predicting race times
Once you have your VDOT, the Riegel formula predicts your times at any distance. The key insight: doubling the distance adds more than double the time because of the fatigue exponent (1.06). A 20:00 5K runner won't run a 40:00 10K — more like 41:30.
The race predictor generates predictions for 1 mile, 5K, 10K, 15K, half marathon, and marathon from any single race result.
Training with VDOT
Your VDOT determines your optimal training paces. Jack Daniels' five training zones (Easy, Marathon, Threshold, Interval, Repetition) are all derived from your VDOT. Running at the right intensity for each session is more important than running more miles at random paces.
Get your personalized training paces from the training paces calculator, or browse coach-prescribed sessions with your VDOT-based paces at Banger Workouts.
How to improve your VDOT
VDOT improves through consistent training over months. The biggest gains come from: running more weekly volume at easy pace (Zone 1), adding one threshold session per week, and one VO2max interval session per week. Most recreational runners can improve 2-3 VDOT points in a 16-week training cycle.