❤️ Health Tools
Free health calculators: BMI, calories, body fat, heart rate zones, due date, sleep, water and age.
Health and Fitness Calculators
These calculators turn common health questions into clear numbers: whether your weight is in a healthy range, how many calories you need, how much body fat you carry, how much water to drink, when to go to bed to wake up between sleep cycles, your training heart rate zones, a pregnancy due date and your exact age. Each one uses a recognised method, such as the WHO's BMI categories, the Mifflin-St Jeor equation for energy needs, the U.S. Navy formula for body fat and the Karvonen method for heart rate zones, and each page explains how the result is calculated.
Use the Numbers as a Starting Point
A formula cannot know your medical history, so treat every result as a general estimate, not a diagnosis. Several measures together give a better picture than one alone: BMI says nothing about muscle, while body fat percentage and waist size do. If a result worries you, or if you have a health condition, talk to a doctor or a nurse.
Private by Design
Health details are personal. Every calculation happens in your own browser, and nothing you enter is sent to a server or saved.