Library · Tools
Every fitness calculator you need
All 13 calculators are fully built and running in the browser — no signup, no gated features.
Total Daily Energy Expenditure
TDEE Calculator
Estimate the calories your body burns in a day based on your activity level.
Body Mass Index
BMI Calculator
Compute your BMI from height and weight.
US Navy method
Body Fat Calculator
Estimate body fat percentage using the US Navy formula.
Epley formula
One Rep Max Calculator
Estimate your 1RM from a submaximal set.
Protein, carbs, fat split
Macro Calculator
Build a macro target based on your goal and calorie needs.
Daily protein target
Protein Calculator
Calculate your daily protein target based on bodyweight and goal.
Hydration target
Water Intake Calculator
Estimate a sensible daily water intake goal.
Run pace and finish time
Pace Calculator
Convert distance, pace and time between each other.
Fat-Free Mass Index
FFMI Calculator
Estimate your fat-free mass index for muscularity benchmarks.
Boer formula
Lean Body Mass
Estimate lean body mass from height, weight and sex.
Devine formula
Ideal Weight Calculator
Estimate ideal bodyweight from height and sex.
Mifflin-St Jeor
Calorie Calculator
Calculate BMR and daily calorie targets by goal.
5-zone model
Heart Rate Zones
Compute your five training heart-rate zones.