Free health calculators for your yoga and fitness goals
Numbers can help you set sensible goals: how much energy your body uses, how much water and protein you may need, and what a healthy weight range looks like for your height. These free calculators give quick estimates. Use them as a starting point, not a diagnosis.
- Cost
- Free, no sign-up
- Works on
- Mobile and desktop
- Results
- Estimates only
Energy and calories
Start here if your goal is weight loss, weight gain or simply eating the right amount for how active you are.
BMR calculator
Estimates your basal metabolic rate: the energy your body uses at complete rest, for breathing, circulation and body temperature.
Open calculatorCalorie calculator
Estimates your daily calorie needs from age, sex, height, weight and activity level, to maintain, lose or gain weight.
Open calculatorWeight and height
Different formulas give slightly different answers. Treat the result as a range, and remember that muscle, build and age all matter.
Ideal weight calculator
Shows a commonly used ideal weight estimate for your height using standard formulas.
Open calculatorHeight weight calculator
Compare your height and weight against a healthy range and track changes over time.
Open calculatorWeight calculator
Estimates a healthy weight range from your height, age and sex.
Open calculatorBody weight calculator
Body weight estimates using several health formulas side by side.
Open calculatorHeight calculator
Height estimates and conversions using standard growth references.
Open calculatorWater, fluids and protein
Useful if you practise in hot weather, sweat a lot, or want to check your protein after strength-focused yoga or gym work.
Water intake calculator
Estimates how much water you may need daily, based on your weight and activity.
Open calculatorLiquid intake calculator
Estimates total fluid needs from all drinks, including tea, milk and buttermilk.
Open calculatorProtein intake calculator
Estimates daily protein needs based on your weight, activity and goal.
Open calculatorBAC calculator
Estimates blood alcohol concentration. An estimate only: never use it to decide whether you can drive.
Open calculatorHow to read the results
They are averages
Formulas are built from large groups of people. Your real needs can be higher or lower.
Watch the trend
How your weight, energy and waist change over weeks tells you more than one number.
Weight is not everything
Two people with the same weight can have very different health. Activity, sleep, diet and waist size matter too.
Ask a professional
Pregnancy, diabetes, kidney or heart disease, and teenagers' growth need advice from a doctor or dietitian.
These calculators open on separate websites and give general estimates for education only. They are not medical advice. See our medical disclaimer.
Calculators: common questions
Are these calculators free?
Yes. They are free to use, with no sign-up.
What is BMR?
Basal metabolic rate: the energy your body uses at complete rest to keep you alive. Your daily needs are higher, depending on activity.
How accurate are calorie calculators?
They give a reasonable starting estimate. Adjust based on how your weight and energy change over a few weeks.
How much water should I drink?
It depends on your size, activity and the weather. Use the water calculator as a guide, and drink more in summer and after sweaty practice.
Can I use these results to plan a diet?
As a starting point, yes. For medical conditions or big changes, speak to a doctor or registered dietitian.
Last updated 24 October 2026.