BMR Calculator
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
Enter details
Result
Fill in the fields to see your result.
Estimate only — not medical or nutritional advice. Individual needs vary; consult a professional before making big changes.
How to use this calculator
- Enter sex, age, height and weight.
- Pick a formula (Mifflin–St Jeor is recommended).
- Read your basal metabolic rate (BMR).
How it works
BMR is the energy your body uses at rest. Mifflin–St Jeor: 10·kg + 6.25·cm − 5·age + 5 (men) or − 161 (women). Harris–Benedict is also offered.
Worked example
Man, 80 kg, 180 cm, 30 y. Mifflin–St Jeor BMR = 1,780 kcal/day.
Tips
- Estimate only — not medical or nutritional advice. Individual needs vary.
Frequently asked questions
BMR vs TDEE?
BMR is at-rest energy; TDEE adds your activity. Use the TDEE calculator for maintenance calories.
Which formula?
Mifflin–St Jeor is generally the most accurate for most people.
Privacy?
Runs entirely in your browser. Your inputs are not saved or transmitted.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.