👟 Running Calculators

Whether you're lacing up for your first 5K or chasing a Boston Marathon qualifying time, data-driven training is the edge that separates good runs from great ones. Our collection of running calculators covers every metric a runner needs -- from daily pace calculations to advanced aerobic capacity estimation.

Train Smarter with Science-Backed Formulas

The cornerstone of our running toolkit is the VDOT Calculator, built on coach Jack Daniels' landmark oxygen-cost research. Your VDOT score is a single number that captures your current fitness level and automatically generates personalised training paces -- easy, marathon, threshold, interval, and repetition -- so every workout has a purpose.

Pair that with the Race Time Predictor (based on Pete Riegel's proven formula) and you can accurately forecast your finish time at any distance from a 5K to an ultra. Input a recent race result and let the maths tell you what you're capable of at your next event.

Plan Your Race Like a Pro

Pacing is where races are won and lost. Our Marathon Pace Calculator and Half Marathon Pace Calculator produce a complete split table -- every kilometre and mile -- so you always know exactly where you should be on course. The Negative Split Calculator helps you structure a two-phase pacing strategy proven to unlock faster finish times.

Running in heat? The Heat Adjustment Calculator quantifies how much slower you should expect to run at different temperatures and humidity levels. Heading into the hills? The Elevation Adjustment Calculator applies Minetti's biomechanical model to give you an equivalent flat pace for hilly routes.

Track Your Progress Over Time

The Age Graded Calculator lets you compare performances across different ages and genders -- perfect for tracking whether you're actually getting faster relative to your age group. And if you train with a power meter, the Running Power Calculator estimates your output in watts from pace, weight, and gradient.

All calculators are free, instant, and work on any device. No sign-up, no ads in your face -- just the numbers you need.