Free fitness calculators

Estimate calories burned during any workout using MET-based formulas. Supports cycling, running, swimming, and more.

Convert between pace, speed, and finish time. Calculate splits for any race distance from 5K to ultra marathon.

Estimate your Functional Threshold Power from a 20-minute or ramp test. Includes power zone breakdown.

Calculate your 5-zone heart rate training system from max HR or lactate threshold. Includes zone descriptions.

Calculate your Body Mass Index with context for athletes. Includes athlete-adjusted interpretation and healthy range guidance.

Estimate your aerobic fitness (VO2 max) from a race result, Cooper test, or field test. Includes fitness category ratings.

Estimate finish times for Sprint, Olympic, 70.3, and Ironman races from your individual swim, bike, and run paces.

Convert swim pace per 100m to finish times for any pool or open water distance. Includes SWOLF and efficiency metrics.

Calculate your Total Daily Energy Expenditure based on height, weight, age, and activity level. Includes athlete-specific multipliers.

Calculate your daily protein, carbohydrate, and fat targets based on your goal — performance, fat loss, or muscle gain.

Estimate your body fat percentage using skinfold or circumference measurements. Includes athlete performance ranges.

Estimate your 1RM from submaximal lifts using the Epley, Brzycki, or Lombardi formula. Includes percentage training table.

Calculate your cycling W/kg ratio and see how you compare to amateur and pro categories. Essential for climbing performance.

Calculate your fluid and sodium needs per hour based on exercise intensity, temperature, and duration. Includes sports drink guidance.

Compare your running time to age-group world records. Get your age grade % and performance category for 5K, 10K, half, or full marathon.

Predict your finish time for any distance from a recent race result using the Pete Riegel formula. Includes full distance comparison table.

Calculate TSS for any workout and plan your weekly training load. Understand your stress-recovery balance before it becomes a problem.

Generate even or negative split plans for 5K to marathon. See exact pace per kilometre or mile to hit your target time.

Power-based or speed-based calorie calculation for cyclists. More accurate than generic tools — includes kJ output and per-hour breakdown.

Plan triathlon brick workouts for Sprint to Ironman. Get this week's session, intensity guidance, and a 6-session progression plan.