Health & Fitness

Calculate your Body Mass Index (BMI) instantly. Free BMI calculator for adults in metric and imperial units, with WHO category breakdown.

Calculate your basal metabolic rate (BMR) and total daily energy expenditure (TDEE) — the calories you burn at rest and with activity.

Calculate daily protein, carbohydrate, and fat targets for cutting, maintaining, or bulking. Supports keto, low-carb, and balanced diets.

Estimate body fat percentage from neck, waist, and hip measurements using the US Navy circumference formula.

Compute ideal body weight using four classic formulas (Devine, Robinson, Miller, Hamwi) plus a healthy-BMI range.

Estimate lean body mass (LBM) using the Boer, James, and Hume formulas. Used for medication dosing and body composition tracking.

Calculate waist-to-hip ratio (WHR), a body shape metric linked to cardiovascular health risk.

Estimate how much water to drink per day based on your weight, activity level, and climate. Returns liters, ounces, and glasses.

Calculate your five training heart rate zones from age and resting heart rate using the Karvonen heart-rate-reserve formula.

Convert between pace, time, and distance. Predict marathon, half-marathon, 10K, and 5K finish times from a shorter race result.

Estimate your one-rep max from a recent set using six common formulas (Epley, Brzycki, Lombardi, Mayhew, O'Conner, Wathen).

Calculate the calorie deficit needed to lose weight by a target date, and project how long realistic deficits will take.

Estimate your pregnancy due date and how many weeks pregnant you are. Supports last menstrual period (LMP), conception date, and ultrasound dates.

Estimate ovulation date and fertile window from your last period and cycle length. Useful for trying to conceive or natural cycle tracking.

Calculate your eating and fasting windows for 16:8, 18:6, 20:4, OMAD, and custom intermittent fasting protocols.

See how much caffeine remains in your body hours after drinking it, and when it's safe to sleep without disruption.

Estimate blood alcohol content based on drinks, body weight, sex, and time. Includes sober-time estimate.

Calculate optimal bedtime or wake-up time based on 90-minute sleep cycles, with 15-minute fall-asleep buffer.

Track accumulated sleep debt over a week and see how many extra hours you'd need to recover.

Estimate your annual carbon footprint in tonnes of CO2 from home energy, driving, flights, and diet.

Convert your dog's age to human years using the modern AVMA-aligned formula — not the outdated 7× myth.

Convert your cat's age to human years using the modern veterinary aging chart, with milestones for kitten, adult, senior, and geriatric stages.

Calculate daily, monthly, and yearly pet food cost based on bag size, price, and daily portion.

Track pickleball scores for singles and doubles. Follows official USAPA rules including server number and side-out logic.

Convert mouse sensitivity between FPS games (Valorant, CS2, Apex, Overwatch). Calculate eDPI and equivalent in-game sensitivity.

Estimate total daily calories burned from BMR plus activity level — the starting point for any nutrition plan.

Daily protein target in grams based on bodyweight and goal (cut, maintain, bulk).

Calculate FTP power-to-weight ratio and find your cyclist classification (recreational to world-class).

Convert total swim time and distance into pace per 100 m or 100 yd, plus split projections.

Convert daily step count to distance (km/mi) and approximate calories burned by walking pace.

Calculate Fat-Free Mass Index — a muscle-mass measure that adjusts for height.

Estimate aerobic fitness (VO2 max) from age and resting heart rate.

Classify your blood pressure reading per the 2017 ACC/AHA guidelines.

Calculate Total/HDL and LDL/HDL cholesterol ratios — stronger CVD predictors than totals.

Find your chronotype and optimal bedtime/wake time based on natural sleep midpoint.

Predict next 3 periods, fertile window, and ovulation from last period and cycle length.

Convert blood glucose between US (mg/dL) and international (mmol/L) units, with category.

Calculate calories burned for any activity using its MET value and your bodyweight.