Calculators for Body Fat, Nutrition & Fitness

Free tools built on validated formulas to help you understand your body, plan nutrition, and set training goals. Pick a calculator below to get started.

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⚖️ Weight & Body Composition

Assess body fat, BMI, and composition metrics to set realistic health goals.

BMI Calculator

Calculate your Body Mass Index (BMI) and find your healthy weight range. Works for adults and children.

Body Fat Calculator

Estimate body fat percentage using the US Navy circumference method. Find your goal weight at a healthy body fat level.

Visceral Fat

Estimate visceral fat area from waist and thigh measurements using a CT-validated model.

FFMI Calculator

Calculate your Fat-Free Mass Index normalized for height. Compare against drug-free athlete ranges.

Ideal Body Weight

Calculate ideal body weight using Devine, Robinson, Miller, and Hamwi formulas.

Muscle Mass

Estimate skeletal muscle mass percentage using the Janssen equation.

Waist-to-Height Ratio

Calculate your waist-to-height ratio (WHtR) and see your NICE central adiposity category, the healthy waist range for your height, and how far you are from the 0.5 boundary. Works in inches or centimeters for adults and children aged 5 and over.

Waist-to-Hip Ratio

Calculate waist-to-hip ratio with gender-specific health risk assessment.

ABSI Calculator

Calculate ABSI to assess abdominal obesity independent of BMI.

Adjusted Body Weight

Calculate adjusted body weight for drug dosing and nutrition when actual weight exceeds ideal body weight.

BAI Calculator

Estimate body fat percentage using hip circumference and height with the Body Adiposity Index.

Frame Size

Determine small, medium, or large body frame from wrist circumference and height.

BRI Calculator

Calculate Body Roundness Index from waist circumference and height to estimate visceral adiposity.

BSA Calculator

Calculate body surface area using Mosteller, Du Bois, and Haycock formulas.

Lean Body Mass

Estimate lean body mass using body fat percentage or the Boer equation.

Ponderal Index

Calculate ponderal index (weight/height³) as an alternative to BMI, especially for infants.

RFM Calculator

Estimate body fat percentage using only height and waist circumference.

Skinfold Body Fat

Estimate body fat percentage using the Jackson-Pollock 3-site skinfold method.

Weight Loss %

Calculate the percentage of body weight lost from starting to current weight.

Navy Body Fat

Calculate body fat percentage using the US Navy circumference method with neck, waist, and hip measurements.

BMI for Women

Calculate BMI with interpretation tailored for women, including healthy range and body composition context.

BMI for Teens

Calculate BMI for teenagers with age- and sex-specific percentile interpretation.

Geriatric BMI

Calculate BMI for adults 65+ with age-appropriate healthy weight ranges.

BMI Weight Loss

Calculate target weight for a goal BMI and how much weight you need to lose.

🔥 Calories & Metabolism

Calculate TDEE, calorie deficits, and metabolic rate for weight management.

🏃 Calories Burned by Exercise

Calories burned walking, running, cycling, swimming, lifting, yoga, and 20+ other workouts, by weight and intensity.

Calories Burned

Calories burned for 30 common exercises by body weight and time, from walking and running to weight lifting, yoga, and pickleball. Uses 2024 Adult Compendium MET values and links to a detailed calculator for each activity.

Swimming Calories

Calories burned swimming by stroke, pace, and body weight. Freestyle, backstroke, breaststroke, butterfly, treading water, and open water, using 2024 Compendium MET values.

Walking Calories

Calories burned walking by pace, distance, and body weight. Covers strolling, brisk walking, power walking, Nordic walking, sand, grass, and walking the dog, with calories per mile and per 10,000 steps.

Running Calories

Calories burned running by pace (4 to 14 mph), distance, and body weight. Includes jogging, cross-country, hill running, and stroller running, with calories per mile, per 5K, and per week.

Treadmill Calories

Calories burned on a treadmill from your exact speed, incline, and body weight, using the ACSM walking and running equations. Shows the extra burn from the incline, vertical climb, and calories per mile.

Incline Walking Calories

Calories burned walking on an incline treadmill, including the 12-3-30 workout. Enter speed, incline, and body weight to see total burn, the extra from the hill, and vertical feet climbed.

Hiking Calories

Calories burned hiking by terrain, grade, and pack weight. Covers easy trails, steep climbs, day hikes with a pack, backpacking, and Nordic poles, using 2024 Compendium MET values.

Rucking Calories

Calories burned rucking from body weight, pack weight, speed, grade, and terrain, using the Pandolf load-carriage equation the military uses. Shows the extra burn from the pack and calories per mile.

Cycling Calories

Calories burned cycling by speed, body weight, and bike type. Covers leisure riding, road speeds from 10 to 20+ mph, commuting, mountain biking, and e-bikes, with calories per mile and an optional power meter input.

Stationary Bike Calories

Calories burned on a stationary or spin bike by watts, effort level, and body weight. Covers upright and indoor bikes, spin classes, virtual rides, and bike intervals.

Air Bike Calories

Calories burned on an air bike (fan bike) by watts, effort, and body weight. Covers steady riding, sprint intervals, and arms-only work.

Elliptical Calories

Calories burned on an elliptical trainer by effort and body weight, with a ski machine option and comparisons with the treadmill and bike.

Stair Climber Calories

Calories burned on a stair climber machine or real stairs by pace and body weight. Covers slow and fast climbing, two steps at a time, running stairs, and going down.

Rowing Machine Calories

Calories burned on a rowing machine by watts, effort, and body weight. Enter the average watts from your monitor for a power-based estimate.

Jump Rope Calories

Calories burned jumping rope by pace, body weight, and time. Covers slow, moderate, and fast skipping, double unders, and general rope work, with calories per jump and weekly totals.

Burpee Calories

Calories burned doing burpees by body weight, time, and style. Covers steady burpee sets and burpee intervals, with calories per burpee and how burpees compare to other bodyweight moves.

Jumping Jacks Calories

Calories burned doing jumping jacks by body weight, time, and effort. Covers warm-up pace, vigorous nonstop jacks, and interval workouts, with calories per jumping jack.

Push-Up Calories

Calories burned doing push-ups by reps, time, body weight, and push-up variation. Uses a rep-based model from measured oxygen use and shows how much of your body weight each variation puts on your hands.

Squat Calories

Calories burned doing squats by reps, time, body weight, and squat type. Covers bodyweight squats with a rep-based model, plus squat circuits, weighted squats, and jump squats.

Plank Calories

Calories burned holding a plank by hold time, sets, body weight, and plank type. Covers standard forearm and high planks and moving plank variations.

Weight Lifting Calories

Calories burned lifting weights by body weight, session length, and training style. Covers general strength training, heavy squats and deadlifts, supersets, and vigorous bodybuilding or powerlifting sessions.

HIIT Calories

Calories burned in a HIIT workout by body weight, time, and intensity. Covers moderate intervals, bike sprints, and vigorous bodyweight circuits such as Tabata, burpees, and mountain climbers.

Circuit Training Calories

Calories burned in circuit training by body weight, time, and effort. Covers light and moderate circuits, bodyweight circuits, supersets, and vigorous circuits with kettlebells and minimal rest.

Kettlebell Calories

Calories burned with kettlebells by body weight, time, and workout type. Covers kettlebell swings, kettlebell circuits, and slower squats and deadlifts, with calories per swing and weekly totals.

Yoga Calories

Calories burned doing yoga by body weight, class length, and style. Covers hatha, vinyasa, hot yoga, sun salutations, power yoga, and high-intensity hatha, with measured results from lab studies.

Pilates Calories

Calories burned doing Pilates by body weight, class length, and format. Covers mat Pilates, reformer classes, general studio sessions, and fast-paced classes with short rests.

Stretching Calories

Calories burned stretching by body weight, time, and type. Covers gentle static stretching, follow-along stretching videos, and active or dynamic mobility routines.

Pickleball Calories

Calories burned playing pickleball by body weight, time on court, and format. Uses a measured value for recreational doubles and a paddle-sport estimate for singles, with results from heart rate and accelerometer studies.

Tennis Calories

Calories burned playing tennis by body weight, time on court, and format. Covers social doubles, hitting practice, standard doubles, general play, and singles, with measured match data.

Basketball Calories

Calories burned playing basketball by body weight, time, and type of play. Covers shooting around, casual non-game play, pickup games, full games, and drills, with results from small-sided game studies.

🥗 Nutrition & Diet

Plan macros, protein intake, hydration, and fasting windows.

💪 Fitness & Training

Optimize workouts with 1RM, heart rate zones, and VO₂ max estimates.

💊 Supplements & Lifestyle

Fine-tune caffeine, creatine, alcohol intake, and longevity habits.

🔧 Tools & Utilities

Measurement conversions and nutrition knowledge quizzes.

🩸 Diabetes & Blood Sugar

Convert glucose units, estimate A1c, and assess insulin resistance and diabetes risk.

😴 Sleep & Recovery

Plan sleep cycles, track sleep debt, and screen for sleep apnea and daytime sleepiness.

❤️ Heart & Cardiovascular

Assess blood pressure, cholesterol, and cardiovascular disease risk.

⚕️ Metabolic Disorders

Screen for metabolic syndrome and related cardiometabolic risk factors.

🚭 Addiction & Recovery

Estimate alcohol intake, nicotine dependence, and track sobriety milestones.

🤰 Pregnancy & Reproductive Health

Calculate due dates, ovulation windows, gestational age, and pregnancy nutrition needs.

🫘 Kidney & Filtration

Estimate GFR, creatinine clearance, albuminuria, and related kidney lab ratios.

Understanding Your Body Composition

Body weight alone does not tell you what that weight is made of. Tracking body fat percentage and lean mass gives better insight than the scale. Fat stored as adipose tissue contains triglycerides your body burns during a calorie deficit.

Metabolic Rate and Energy Balance

Your Resting Metabolic Rate (RMR) is calories burned at rest for breathing, cell repair, and organ function. Total Daily Energy Expenditure (TDEE) adds movement, exercise, and digestion. Eating below TDEE supports fat loss; eating above with resistance training supports muscle gain.

Common Misconceptions About Fat Loss

Fat does not turn into muscle. They are separate tissues, though you can lose fat and gain muscle over the same period. Spot reduction is a myth: genetics decide where fat comes off first. Crash diets cause quick loss but often sacrifice muscle and are hard to sustain.