Running & Cardio

Pace, race-time prediction, heart-rate zones and calories burned.

• Running Pace Calculator

  Convert between running pace, time and distance in one tool with a mile or kilometre toggle, plus a mile-by-mile or kilometre-by-kilometre split table.

• Race Time Predictor

  Predict your 5K, 10K, half-marathon and marathon finish times from one recent race result using Peter Riegel's published endurance formula.

• Heart Rate Zone Calculator

  Calculate five heart-rate training zones from age and resting heart rate using the Karvonen formula, with an optional lab-tested max HR override.

• VO2max Estimator

  Estimate your VO2max from either the 12-minute Cooper run test or the 1-mile Rockport walk test, toggled in one calculator with published field-test formulas.

• Calories Burned Calculator

  Estimate calories burned for walking, running, cycling, swimming, weights and 35+ other activities using MET values from the 2024 Compendium of Physical Activities.

• Treadmill Incline Pace Converter

  Convert a treadmill's incline and speed into the equivalent flat-ground running or walking pace using the ACSM metabolic equations for oxygen cost.

• Cycling Power-to-Weight Calculator

  Calculate your cycling watts-per-kilogram ratio from FTP or any power number and body weight, benchmarked against Coggan's published rider-category chart.

• Steps to Calories and Distance Calculator

  Convert a step count into estimated distance, walking time and calories burned, using a stride length estimated from your height and MET-based walking values.

• Swim Pace Calculator

  Convert a swim distance and time into your pace per 100 metres or yards, plus a split-time table for 100 through 1,500 to help plan pool sets.

• Max Heart Rate Calculator

  Estimate your maximum heart rate with a toggle between the Tanaka (2001) formula and the traditional 220-minus-age formula, shown side by side.

• Cycling Speed-to-Power Estimator

  Estimate the power (watts) needed to hold a target cycling speed, split into rolling resistance, aerodynamic drag and climbing, using a physics-based model.