Calculators
Health & Nutrition
BMI, calories, macros, sleep and body measurements. · 38 tools
Understand your numbers before changing your habits. These calculators estimate energy needs (BMR and TDEE), set targets (calorie deficit, macros, protein, water), and track body measurements (BMI, body fat, waist ratios, ideal weight). Each page explains which formula it uses and where the limits of the estimate lie.
None of this is medical advice — the tools are a starting point for a conversation with a doctor, dietitian or coach.
Alcohol CalculatorCalculate weekly alcohol units and annual cost.Army Body Fat CalculatorFree Army body fat calculator using the classic AR 600-9 tape test formulasBaby Sleep Calculator — Sleep Needs by AgeCalculate how much sleep a baby or child needs by age.Blood Alcohol CalculatorCalculate BAC with Widmark formula and estimate time to sober up.Blood Pressure CalculatorCalculate mean arterial pressure (MAP) and pulse pressure from systolic and diastolic r…BMI CalculatorPopularCalculate BMI and ideal weight. Colour-coded classification.BMR CalculatorCalculate your basal metabolic rate (BMR) — energy burned at rest — with the Mifflin–St…Body Fat CalculatorEstimate your body fat percentage with the US Navy method from body measurements.Body Surface Area CalculatorCalculate body surface area (BSA) with the Mosteller formula from height and weight.Calorie CalculatorPopularDaily calorie needs (TDEE) and basal metabolic rate (BMR).Calorie Deficit CalculatorCalculate the daily calorie deficit needed for a target weekly weight loss and your goa…Child Height Predictor — Adult HeightEstimate your child's adult height from parents' heights.Due Date CalculatorCalculate due date, pregnancy weeks and important milestones.Fiber Intake CalculatorCalculate your daily fiber needs based on calorie intake and compare to the recommendat…HbA1c CalculatorConvert your long-term blood sugar (HbA1c) into estimated average glucose in mmol/L and…Heart Rate ZonesMax heart rate and all 5 training zones in bpm.Ideal Weight CalculatorCalculate your ideal weight from height and sex.Iron CalculatorTrack daily iron intake, interpret ferritin levels and identify deficiency symptoms.Lean Bulk CalculatorFree lean bulk calculator: find your bulking calories and daily protein target for muscle Macro CalculatorSplit your daily calories into macronutrients: protein, carbohydrates and fat in grams.Maintenance Calorie CalculatorFree maintenance calorie calculator: find how many calories you need to maintain your currOvulation CalculatorEstimate your ovulation day and fertile window from your cycle.Protein Calculator — Daily Protein NeedsCalculate how much protein you need daily by weight and goal.Pulse Pressure CalculatorFree pulse pressure calculatorRecovery Time Calculator — Rest DaysCalculate how long muscles need to recover after training by intensity.Running Pace CalculatorPace, time or distance — race times from 5 km to marathon.Salt Intake CalculatorConvert sodium to salt and compare to the daily recommendation.Sleep Needs CalculatorSee how many hours of sleep you need by age and compare it to your current sleep.Sports Hydration CalculatorCalculate how much fluid you lose and need during exercise by sweat rate.Steps to Calories CalculatorCalculate how many calories your walking steps burn based on your body weight.Steps to Distance CalculatorCalculate how far your steps cover based on your stride length, in kilometres and metres.Sugar Intake CalculatorCalculate your recommended maximum daily added sugar by WHO guidance, in grams and teas…TDEE CalculatorPopularFree TDEE calculator: find your total daily energy expenditure with the Mifflin-St Jeor equationVO2max CalculatorEstimate your maximal oxygen uptake (VO2max) from the distance run in the 12-minute Coo…Waist-to-Height Ratio CalculatorCalculate your waist-to-height ratio (WHtR).Waist-to-Hip Ratio CalculatorCalculate your waist-to-hip ratio (WHR), an indicator of abdominal fat and health risk.Water Intake Calculator — Daily NeedsCalculate how much water you should drink per day by weight, exercise and weather.Weight Loss Timeline CalculatorCalculate how long it takes to reach your goal weight with your chosen daily calorie de…
How to choose
- Energy and weight
- Start with TDEE to learn your maintenance calories, then use the deficit or lean-bulk calculator to set a target.
- Body measurements
- BMI is quick but crude; body-fat and waist-to-height ratio give a fuller picture, especially for athletes.