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Health calculators

Health11

Health calculators for BMI, BMR, TDEE, macros, body fat, ideal weight, hydration and pregnancy due dates.

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Calculate your Body Mass Index from weight and height in metric or imperial units, with WHO categories and the healthy weight range for your height.

Estimate your basal metabolic rate; the calories your body burns at complete rest; using Mifflin-St Jeor with a revised Harris-Benedict comparison.

Work out your total daily energy expenditure from BMR and activity level; the calories needed to maintain your current weight.

Turn your TDEE into a daily calorie target for fat loss, with expected weekly and monthly progress at your chosen deficit.

Split your daily calories into carbohydrate, protein and fat gram targets using adjustable percentages and standard energy densities.

Find your daily protein target from body weight and activity level, comparing the RDA baseline with evidence-backed ranges for active adults.

Estimate body fat percentage with the US Navy circumference method using height, neck and waist measurements (plus hips for women).

See ideal body weight estimates from the Devine and Robinson clinical formulas for your height and sex, presented side by side in kilograms.

Estimate daily fluid needs from body weight plus exercise minutes, using a 33 ml/kg baseline with additions for training sweat loss.

Estimate your due date from the first day of your last menstrual period using Naegele’s rule, plus your current gestational week and trimester.

Check your waist-to-height ratio against the WHO 0.5 boundary to assess central adiposity; a stronger cardiometabolic signal than BMI alone.