VDOT Running Calculator — Training Paces (Jack Daniels)

VDOT is a numerical value describing running fitness, developed by coach Jack Daniels. It is closely related to VO2max (maximal oxygen uptake) but estimated indirectly from race results. A higher VDOT means better aerobic capacity. It is used to prescribe training zones and paces.

Enter your race distance and finish time. The calculator estimates the oxygen demand at your race pace, the percentage of VO2max you used, and divides one by the other to get VDOT. A genuine race effort on 5K or 10K in good conditions gives the most reliable result.

Easy pace uses about 59–74% of VO2max — you should be able to hold a conversation comfortably. At VDOT 40 this is approximately 7:00–7:30 min/km; at VDOT 50 about 5:50–6:20 min/km. Most weekly volume (70–80%) should be at Easy pace.

Threshold pace corresponds to the lactate threshold — about 88% of VO2max. It feels 'comfortably hard': you can speak short sentences but not hold a conversation. Runs at T pace should last 20–40 minutes or be broken into cruise intervals. T-pace training improves the lactate threshold and running economy.

Interval pace is about 97–100% of VO2max — very intense, sustainable only for 3–8 minutes. Used in repeats of 800–1200 m with jogging recovery. Interval training produces the greatest gains in VO2max.

Repetition pace is about 105–110% of VO2max — faster than I-pace. Used for short repeats of 200–400 m with full recovery. R-pace training improves running economy, speed and running form rather than aerobic capacity.

VO2max is a laboratory measurement of maximum oxygen uptake (ml/kg/min). VDOT is calculated indirectly from race results — it differs slightly from lab VO2max due to individual running economy. For practical training purposes VDOT is sufficient and more accessible.

Race performance depends on physiology (VO2max, lactate threshold), running economy and fatigue resistance. Shorter races (5K) stress the aerobic system differently than long ones (marathon). Ideally your VDOT from different distances should be consistent. Discrepancies reveal strengths or weaknesses.

VDOT 30–35: recreational runner. VDOT 40–45: well-trained amateur. VDOT 50–55: advanced amateur (sub-20 min 5K). VDOT 60–65: national elite. VDOT 70+: world elite (e.g. Kipchoge ~85). Women typically score 10–12 VDOT points lower at the same competitive level.

The calculator is most accurate for distances between 5K and the marathon. For shorter distances (< 1 mile) anaerobic components have a large influence and can inflate the estimated VDOT. For best results use official race results rather than training runs.