13 free tools
Health calculators
Body measures, energy needs, pregnancy dates and weather-related heat stress, each with its formula and source.
These tools use published equations, such as WHO BMI bands and the Mifflin-St Jeor energy equation. Each page names the equation and links the source it comes from.
Results describe populations, not you. They cannot diagnose anything; use them to prepare questions for a doctor or dietitian.
All tools 13
BMI, BMR and TDEE, body fat, macros, protein, kidney function, pregnancy, pace and heat stress.
BMI Calculator
Work out an adult BMI and compare it with WHO, Asian and Indian cut-offs, plus the weight range each calls normal for your height.
BMR & TDEE Calculator
Estimate the energy you use at rest and in a whole day, with the formula named and a range for your activity level.
Body Fat Calculator
Estimate body fat from tape measurements or BMI, with fat and lean mass and a cited category table.
Ideal Weight Calculator
See four historical ideal-weight formulas and BMI-based weight ranges side by side for your height.
Protein Intake Calculator
Estimate daily protein for healthy Indian adults from ICMR-NIN 2020 figures, including pregnancy and breastfeeding.
Pregnancy Conception Calculator
Estimate conception, ovulation, fertile-window and due dates from an LMP or due date.
Body Surface Area Calculator
Estimate body surface area in m² from height and weight by the Mosteller, Du Bois, Haycock and Gehan–George formulas.
eGFR Calculator
Estimate kidney filtration (eGFR) from serum creatinine with the race-free CKD-EPI 2021 equation and see the GFR category.
Heat Index Calculator
Find how hot it feels from the temperature and humidity, in °C and °F, with the NWS risk level.
Macro Calculator
Turn a daily calorie figure into grams of protein, carbohydrate and fat, with fibre guidance and a per-meal split.
Pace Calculator
Work out pace, time or distance from the other two, with speed, splits and race finish times.
Pregnancy Weight Gain Calculator
View IOM pregnancy weight-gain reference ranges by BMI category and pregnancy week.
Wind Chill Calculator
Find how cold it feels in the wind, in °C and °F, with the NWS wind chill formula.
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Every tool explains its method and sources. See how we test the maths, or report a possible error.