Health & Fitness Calculators
BMI, calorie needs and body metrics based on published clinical formulas.
A1C Calculator (A1C to Average Blood Glucose)Convert A1C to estimated average glucose (eAG) in mg/dL and mmol/L, or the reverse, using the ADAG study formula. Not a substitute for medical advice.Alcohol Unit Calculator (UK)Calculate UK alcohol units from drink volume and ABV, then compare your weekly total to the CMO's 14-unit guideline. Estimates only, not medical advice.BAC CalculatorEstimate blood alcohol concentration with the Widmark formula from sex, weight, drinks, and hours elapsed. Educational only; never drive after drinking.BMI CalculatorCalculate your BMI from height and weight in kg/cm or lb/ft. See your WHO weight category and the healthy weight range for your height, formula included.BMR CalculatorCalculate BMR and total daily energy expenditure with the Mifflin-St Jeor equation. See calorie needs at every activity level, in metric or imperial units.Body Fat CalculatorEstimate body fat percentage from neck, waist and height (plus hip for women) using the U.S. Navy method. See fat mass, lean mass and your ACE category.Body Shape CalculatorEnter bust, waist and hip measurements to find your body-shape category (hourglass, pear, apple or rectangle) and see the bust-to-hip and waist-to-hip ratios.Body Surface Area CalculatorCalculate body surface area (BSA) in square meters using the Mosteller and Du Bois formulas, in metric or imperial units. Formulas and citation included.Calorie Deficit CalculatorTurn your TDEE, current weight, goal weight and chosen deficit into the calories to eat daily, an estimated weekly weight change, and weeks to reach goal.Calories Burned CalculatorEstimate calories burned during walking, running, cycling or swimming using published MET values and body weight. Formula and source shown.Child Growth Percentile CalculatorEstimate a child's weight or height percentile from WHO (0-2y) and CDC (2-20y) growth reference data. Not a substitute for a pediatrician's own growth chart.Child Height PredictorEstimate a child's adult height from both parents' heights using Tanner's mid-parental method, with the ±8.5 cm range shown as a wide approximation.FFMI CalculatorCalculate FFMI and normalized FFMI from weight, height and body fat percentage, with interpretation bands and the natural-limit research behind the numbers.Heart Rate Zone CalculatorSee your heart rate training zones from age using the 220-age or Tanaka formula, plus Karvonen zones when you add a resting heart rate.Ideal Weight CalculatorEstimate ideal body weight from height using the Devine, Robinson, Miller and Hamwi formulas, plus a BMI-based healthy weight range, metric or imperial.Lean Body Mass CalculatorEstimate lean body mass with the Boer, James and Hume formulas, or from a known body fat percentage. Compare all three side by side, metric or imperial.Macro CalculatorConvert daily calories into protein, carb and fat grams using a balanced 40/30/30 split, low-carb or high-protein presets, or your own custom percentages.Max Heart Rate CalculatorEstimate your maximum heart rate with four published formulas: the classic 220-age rule, Tanaka, Gulati (for women) and Nes. See how they compare by age.Army Body Fat CalculatorEstimate body fat with the US Army's original AR 600-9 tape formula and compare it to the age-based maximum. Explains how the 2024 one-site test differs.One Rep Max CalculatorEstimate your one-rep max from weight and reps using the Epley formula, compared against Brzycki, plus a percent-of-1RM table for training loads.Running Pace CalculatorCalculate running pace, finish time, or distance from any two of the three. Pace shown per kilometer and per mile, with common race distances built in.Pregnancy Weight Gain CalculatorFind your recommended total pregnancy weight gain by pre-pregnancy BMI, using the IOM (2009) guidelines for singleton and twin pregnancies.Protein Intake CalculatorCalculate daily protein needs in grams from body weight and activity goal, from the 0.8 g/kg RDA baseline up to sports-nutrition ranges, split across meals.Sleep Cycle CalculatorFind bedtimes or wake-up times based on 90-minute sleep cycles plus 15 minutes to fall asleep, counting back from a wake time or forward from bedtime.Standard Drink CalculatorCalculate grams of pure alcohol from drink volume and ABV, convert to standard drinks in the US, UK, Canada or Australia. Estimates only, not medical advice.TDEE CalculatorCalculate your TDEE with the Mifflin-St Jeor equation and see cut, maintain and bulk calorie targets at every activity level, in metric or imperial units.VO2 Max CalculatorEstimate VO2 max from resting heart rate ratio, the Cooper 12-minute test, or a 1.5-mile run time, then see your fitness category by age and sex.Waist to Height Ratio CalculatorCalculate your waist-to-height ratio and see general risk guidance based on the widely cited 0.5 boundary and the UK NICE 2022 cutoffs, metric or imperial.Water Intake CalculatorEstimate daily water intake from body weight and exercise using the common 30-35 mL/kg heuristic, shown in liters, US fluid ounces and cups.