Free tool
VDOT Running Calculator
Calculate your VDOT and training pace zones based on Jack Daniels' Running Formula. Enter a race result to get personalized training paces for Easy, Marathon, Threshold, Interval, and Repetition zones.
Calculate your VDOT
Enter your best race result to calculate VDOT and training paces.
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What is VDOT?
VDOT is a measure of running fitness developed by legendary coach Jack Daniels. It is not the same as VO2max — VDOT represents your “effective VO2max,” combining your aerobic capacity with your running economy into a single number.
Your VDOT is calculated from a recent race result. A higher VDOT means better running fitness. From your VDOT, Daniels' tables determine the optimal training paces for five distinct training zones, each targeting a specific physiological adaptation.
What are the training zones?
Recovery and base-building runs. Comfortable pace where you can hold a conversation. 65–79% of max HR. Most of your weekly mileage should be at this pace.
Marathon race pace. Comfortably hard — sustainable for 2–4 hours depending on fitness. Used for long tempo segments and marathon-specific workouts.
Lactate threshold pace, also known as tempo pace. Comfortably hard effort sustainable for about 60 minutes in a race. Improves endurance and lactate clearance.
VO2max pace for intervals of 3–5 minutes (800m–1600m repeats). Hard effort that builds aerobic capacity. Run with equal recovery jog between repeats.
Fast repeats of 200m–400m to improve running economy and speed. Very fast but not all-out. Full recovery between repeats.
What to do with your VDOT
Knowing your VDOT is only useful if you apply the paces correctly. Here's how each zone fits into a typical training week:
Most of your running should be at Easy pace. It feels slow, but that's the point — it builds your aerobic base without accumulating excess fatigue. If you can't hold a conversation, you're going too fast.
Run at Easy pace but extend the distance. For marathon preparation, some portions can be done at Marathon pace. The long run develops endurance and teaches your body to burn fat efficiently.
20-40 minutes of sustained effort at Threshold pace, or cruise intervals like 3x10 min at T pace with 2 min jog recovery. This is your bread-and-butter quality workout — it raises your lactate threshold.
3-5 minute repeats at Interval pace (e.g. 5x1000m) with equal-duration recovery jog. Builds VO2max — your aerobic ceiling. Don't schedule on consecutive days with threshold sessions.
Short, fast 200-400m repeats at R pace with full recovery between efforts. Improves running economy and neuromuscular coordination. Can be combined with an easy day if the total volume is low.
Golden rule: never do two hard sessions on consecutive days. Easy days between quality workouts are what make the hard days count.
Want automatic VDOT from every workout?
STAS automatically calculates your VDOT from race results synced from your sports watch via Intervals.icu. Every time you run a race or time trial, your VDOT and pace zones are updated automatically.
Your AI coach in ChatGPT uses these pace zones to create personalized training plans, monitor your progress, and adjust workouts based on your current fitness level.
No manual input needed. Connect your Garmin, COROS, Polar, or Suunto — STAS handles the rest.
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