Quick answer: Free health calculators for BMI, calories, sleep, water intake and age. Simple, science-based tools for everyday wellness.
All Health Calculators (10)
Age Calculator →Free age calculator: enter your date of birth to get your exact age in years, months and days, plus total days lived.Health
BMI Calculator - Body Mass Index →Free BMI calculator: enter weight and height to get your Body Mass Index and see the healthy weight range.Health
Calorie Calculator →Free calorie calculator: enter age, weight, height and activity to get your daily calorie target for losing, maintaining or gaining weight.Health
BMR Calculator - Basal Metabolic Rate →Free BMR calculator: estimate basal metabolic rate with the Mifflin-St Jeor equation and see daily calorie needs for five activity levels.HealthBody Fat Percentage Calculator →Free body fat percentage calculator: US Navy tape-measure method from waist, neck, hip and height, plus a BMI-based estimate and fitness categories.HealthTDEE Calculator: Daily Calorie Needs →Free TDEE calculator: estimate your total daily energy expenditure with Mifflin-St Jeor, plus weight-loss and muscle-gain calorie targets.Health
Daily Water Intake Calculator →Free water intake calculator: enter your weight and activity level to get your daily water target in litres and glasses.Health
Sleep Calculator →Free sleep calculator: enter your alarm time to get ideal bedtimes based on 90-minute sleep cycles, or reverse it.HealthOne Rep Max Calculator: 1RM & Training % →Free one rep max calculator: compare 6 formulas (Epley, Brzycki, Lombardi...) for your 1RM, with training percentages from 90% to 50%. Instant.HealthRunning Pace Calculator: Min/Km & Race Time →Free running pace calculator: solve for pace, time or distance, convert min/km, min/mile, km/h and mph, and get 5K to marathon race projections.Health
Frequently asked questions
Are these health calculators free?
Yes, all health calculators are completely free to use.
Which health metrics can I check?
BMI with WHO categories, daily calorie needs, ideal bedtimes from sleep cycles, daily water intake, and exact age.
Is the BMI calculator accurate?
It uses the standard BMI formula and WHO cut-offs. BMI is a screening tool, not a diagnosis, so pair it with other measures.
Do I need an account?
No, every calculator works instantly with no sign-up.