Enter any recent race distance and time. We return your VDOT (Jack Daniels' unified fitness metric) plus every training pace zone — easy, marathon, threshold, interval, repetition. Then turn it into a full plan with one click.
VDOT is the VO2 running equivalent developed by Jack Daniels. It converts any race performance into a single fitness number, which maps back to precise training paces. A runner with VDOT 50 has E-pace 5:10/km, M-pace 4:42, T-pace 4:22, I-pace 4:02, R-pace 3:47 — regardless of whether their best race is a 5K or a marathon.
Within 1 VDOT point if the input race was recent (<6 weeks), run in good weather, on an accurate course, and you were rested. Fresh 10K results are most reliable.
No — the calculator + all 5 training paces are free. Paid tier adds unlimited plan history and advanced analytics.
Use a time trial — 3K or 5K solo at the hardest sustainable effort. Or enter a hard segment effort from Garmin. Get-Split can also estimate from VO2max + LTHR if you don't have race data.
VDOT is performance-derived (from your race time); VO2max is lab- or watch-estimated. VDOT is more practical for setting training paces because it reflects running economy, not just aerobic capacity.
Yes — VDOT gives you M-pace (marathon pace) directly. For a marathon PR attempt, aim to train at the pace implied by your GOAL VDOT, not your current one, if the gap is <4 points.