A VDOT calculator is a running performance tool developed by legendary running coach Jack Daniels. VDOT is a measure of running fitness derived from race performance that estimates VO2 max while accounting for running economy. By entering a recent race time and distance, the calculator outputs a VDOT value that is then used to establish training paces for easy runs, marathon pace, threshold runs, interval training, and repetition pace workouts. The VDOT system allows runners of all abilities to train at the right intensity relative to their current fitness level.
Jack Daniels’ VDOT system is published in the internationally recognized book Daniels Running Formula and has been adopted by coaches and runners worldwide. The VDOT calculator eliminates guesswork from training pace assignment, ensuring athletes train hard enough to stimulate adaptation without exceeding recovery capacity. As fitness improves and race times decrease, the VDOT value increases and training paces adjust accordingly. Online VDOT calculators are freely available through Running for Life, the Jack Daniels Running Calculator, and major running training platforms. Whether you are preparing for a 5k or a marathon, using a VDOT calculator to set evidence-based training paces is one of the most effective investments in structured running improvement.