BMI, ideal weight, BMR, TDEE, and body measurement calculators. Browse our free body metrics tools below — all calculators are instant, accurate, and require no sign-up.
Adjusted Body Weight Calculator — Calculate adjusted body weight (AjBW) from actual weight, Devine ideal body weight, and a selected correction factor commonly used in dosing and nutrition workflows.
Ape Index Calculator — Calculate the ratio and difference between arm span and height.
BMI Calculator — Calculate your Body Mass Index (BMI), see your WHO weight category, healthy weight range for your height, and understand what your BMI means for your health.
BMI Prime Calculator — Free BMI Prime calculator. Calculate your BMI Prime ratio — a normalized version of BMI where 1.0 is the upper limit of normal weight — for a clearer picture of your weight status.
BMR Calculator — Cunningham Equation — Calculate your Basal Metabolic Rate using the Cunningham equation, a lean-mass-based estimate often used for athletes and highly active individuals.
BMR Calculator — Harris-Benedict Equation — Calculate your Basal Metabolic Rate using the revised Harris-Benedict equation (1984). Estimate daily calorie needs at rest for weight management and nutrition planning.
BMR Calculator — Katch-McArdle Formula — Calculate your Basal Metabolic Rate with the Katch-McArdle formula using lean body mass. Useful for individuals who know their body fat percentage. Includes TDEE estimates.
BMR Calculator — Mifflin-St Jeor Equation — Calculate your Basal Metabolic Rate using the Mifflin-St Jeor equation, a widely used BMR formula for the general population. Get TDEE estimates for standard activity levels.
Ideal Body Weight Calculator (Devine Formula) — Calculate your ideal body weight using the Devine formula — the most commonly used IBW calculation in clinical medicine for drug dosing, nutrition planning, and tidal volume estimation.
Ideal Body Weight Calculator (Hamwi Formula) — Calculate your ideal body weight using the Hamwi formula (1964). The oldest major IBW equation, widely used in clinical dietetics with the highest per-inch weight increment.
Ideal Body Weight Calculator (Miller Formula) — Calculate your ideal body weight using the Miller formula (1983). Gives the highest IBW estimates among the four major formulas — a more generous reference weight for your height.
Ideal Body Weight Calculator (Robinson Formula) — Calculate your ideal body weight using the Robinson formula (1983). A refined clinical IBW equation that gives slightly higher estimates than Devine for most heights.
TDEE Calculator — Total Daily Energy Expenditure — Calculate your Total Daily Energy Expenditure (TDEE) using four BMR formulas. Get estimated calorie targets for weight loss, maintenance, and muscle gain based on your activity level.
Waist-to-Height Ratio Calculator — Calculate your waist-to-height ratio (WHtR) as a quick screening measure for central adiposity and cardiometabolic risk. A common rule of thumb is to keep waist below half your height.
Waist-to-Hip Ratio Calculator — Calculate your waist-to-hip ratio (WHR) as a quick screen for abdominal fat distribution using common WHO action thresholds.