Work out what you burn and what to eat, what a tape measure says about body composition, how much to drink, which heart rate zone you are training in, when to go to bed, what a due date is likely to be and what pace a target time requires. Every figure is arithmetic from published equations, computed on your own machine — these are estimates, not medical advice or a diagnosis.
Estimate body fat percentage from neck, waist and hip measurements with the US Navy method, plus lean mass.
Open toolFind your resting metabolism, your maintenance calories and the daily target a lose, hold or gain goal means.
Open toolEstimate a due date from a last period, a conception date or an IVF transfer, with trimester and milestone dates.
Open toolZone 1 to 5 training ranges with the Karvonen method, and the four published maximum heart rate formulas side by side.
Open toolAll four classic ideal body weight formulas for your height, alongside the healthy BMI band and why they disagree.
Open toolTurn a calorie target into grams of protein, fat and carbohydrate, with preset splits and a per-meal breakdown.
Open toolSolve for pace, time or distance, with even-pace kilometre splits and Riegel race predictions from the same effort.
Open toolThe bedtimes or alarm times that land on a whole number of ninety-minute sleep cycles, with the sleep each one gives.
Open toolA daily fluid target from body weight, climate, training and pregnancy, split into what comes from drinks and what comes from food.
Open toolThe BMI calculator lives with the everyday calculators, because that is where people look for it. Body fat percentage is the more useful number of the two: BMI cannot tell muscle from fat, so a trained body can read as overweight while carrying very little fat.
Open the BMI Calculator