How to use the Health & Fitness Calculator
- Choose a calculator tab.
- Pick your units (kg + cm, kg + feet or lb + feet) and enter your details.
- Press “Calculate” to see your results and what they mean.
Which calculator should I use?
- Calorie Calculator: how many calories to eat to maintain, lose or gain weight.
- BMI Calculator: a quick screening of weight relative to height.
- BMR Calculator: calories your body burns at complete rest.
- TDEE Calculator: total calories you burn per day including activity.
- Macro Calculator: daily protein, carbohydrate and fat targets.
- Protein Calculator: daily protein needs based on activity and goal.
- Calorie Deficit Calculator: daily calories for a chosen rate of weight loss.
- Ideal Weight Calculator: weight ranges from four common formulas and BMI.
Formula used
BMR is estimated with the Mifflin-St Jeor equation, which research has found to be among the most accurate for healthy adults: men: 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5; women: 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161.
Daily energy needs (TDEE) are BMR multiplied by an activity factor: 1.2 (sedentary), 1.375 (light), 1.55 (moderate), 1.725 (very active), 1.9 (extra active).
Limits of these estimates
Formulas describe averages. Your real needs can differ by 10% or more depending on body composition, genetics, medical conditions and medications. Use the result as a starting point, track your progress for a few weeks and adjust. Pregnant or breastfeeding women, children, and people with medical conditions should ask a doctor or registered dietitian.
Frequently asked questions
Are these calculators accurate?
They use well-established formulas, but they give estimates. Individual results vary.
Is my data saved?
No. Calculations run in your browser and nothing you enter is stored or sent to us.
Can I use kg with feet, or pounds?
Yes. Choose “kg + feet” to enter kilograms with height in feet and inches, or “lb + feet” for pounds.