Nutrition calculators
Every nutrition calculator — each built on a published, peer-reviewed formula, with the sources cited on the page.
- TDEE Calculator — Total Daily Energy Expenditure
Estimate your total daily energy expenditure (TDEE) and BMR with the Mifflin–St Jeor, Katch–McArdle or revised Harris–Benedict equations. Free, no sign-up.
- Macro Calculator — Protein, Fat & Carb Targets
Free macro calculator: set protein by bodyweight (1.6–2.2 g/kg, per Morton et al. 2018), choose a fat percentage, and get gram and calorie targets for each macro.
- Calorie Deficit Calculator — Weight-Loss Timeline
Free calorie deficit calculator: estimate weekly weight loss and a timeline to your goal using the 7,700 kcal/kg heuristic, with a safety cap at 25% of your TDEE.
- BMI Calculator — Body Mass Index & WHO Category
Free BMI calculator with WHO categories (underweight to obesity class III), metric and imperial inputs, and an honest explanation of BMI's limits for muscular and athletic builds.
- Body Fat Calculator — US Navy Circumference Method
Free body fat calculator using the US Navy circumference method (Hodgdon & Beckett 1984). Tape-measure inputs, metric and imperial, with the ±3–4 point error band shown honestly.
- Ideal Weight Calculator — Devine, Robinson, Miller & Hamwi
Free ideal weight calculator reporting the range across the Devine, Robinson, Miller and Hamwi formulas, framed honestly as historical estimating equations rather than health targets.
- BMR Calculator — Basal Metabolic Rate
Free BMR calculator using Mifflin–St Jeor (default), Katch–McArdle and revised Harris–Benedict equations, with clear guidance on which to trust.
- Lean Body Mass Calculator — Boer Formula
Free lean body mass calculator using the Boer formula, with an optional body-fat override for a direct calculation. Metric and imperial.
- FFMI Calculator — Fat-Free Mass Index
Free FFMI calculator (fat-free mass index) with the Kouri height adjustment — the muscularity metric from the classic study of steroid-free bodybuilders.
- Water Intake Calculator — Daily Hydration Guideline
Free water intake calculator based on EFSA adequate intakes (2.0 L women / 2.5 L men total water) with an exercise allowance from published sweat-rate ranges.
- Calories Burned Calculator — MET Method
Free calories burned calculator using the MET method (kcal/min = MET × 3.5 × kg ÷ 200) with activity values from the Compendium of Physical Activities.
- Steps to Calories Calculator
Free steps-to-calories calculator: stride length from your height, distance from your steps, and energy from published walking MET values. Clearly labelled as a rough estimate.
- Creatine Calculator — Loading & Maintenance Dose
Free creatine dosage calculator: optional loading at 0.3 g/kg/day for 5–7 days and 3–5 g/day maintenance, per the ISSN position stand (Kreider 2017).