Free health calculators
BMI, calories, body fat, due date and ovulation calculators.
- 100% free
- No sign-up
- 7 tools
All Health tools
- BMI calculatorBody mass index in metric or imperial
- Calorie calculatorDaily calories to keep, lose or gain weight
- BMR calculatorCalories your body burns at rest
- Body fat calculatorBody fat percentage from tape measurements
- Due date calculatorPregnancy due date and week by week
- Ovulation calculatorFertile days and next periods
- Water intake calculatorHow much water to drink each day
About Health tools
Quick, private health estimates. Check your body mass index, work out how many calories you need a day to keep, lose or gain weight and how many your body burns at rest, estimate body fat from a few tape measurements, find a pregnancy due date and how far along you are, see your fertile days and next periods, and how much water to drink each day. Use metric or imperial units. Everything is worked out in your browser, so nothing about your body or health leaves your device.
Frequently asked questions
Are these health calculators free?
Yes, completely free with no sign-up and no limits.
Is my health information stored or sent?
No. Every calculator runs in your browser. Your weight, dates and other details are never uploaded or saved by us.
How accurate are the results?
They use the standard formulas doctors and dietitians use, such as Mifflin-St Jeor for calories and Naegele’s rule for due dates. They are estimates for healthy adults and don’t replace advice from a doctor.
Can I use pounds and feet?
Yes. Every calculator that asks for weight or height lets you switch between metric and imperial units.