BMR Calculator — Basal Metabolic Rate
Calculate your BMR (Basal Metabolic Rate) — calories your body burns at rest. Free online BMR calculator using Mifflin-St Jeor formula.
How to Use
- Select Metric (kg/cm) or Imperial (lbs/in) using the toggle at the top.
- Select your gender and adjust your age, weight, and height using sliders.
- Your BMR and TDEE values update instantly. Use activity-adjusted TDEE to plan your calorie intake.
Formula
Mifflin-St Jeor Formula (most accurate):
Men: BMR = (10 × kg) + (6.25 × cm) − (5 × age) + 5
Women: BMR = (10 × kg) + (6.25 × cm) − (5 × age) − 161
Example Calculation
Example: Male, 70 kg, 170 cm, 28 years
| Calculation Step | Value |
|---|---|
| 10 × 70 (weight) | 700 |
| 6.25 × 170 (height) | 1062.5 |
| 5 × 28 (age) | 140 |
| Gender constant | +5 |
| BMR = 700 + 1062.5 − 140 + 5 | 1,627 kcal/day |
Frequently Asked Questions
BMR (Basal Metabolic Rate) is the minimum number of calories your body needs to perform basic life functions at complete rest — breathing, blood circulation, cell production.
Men typically have more muscle mass and less body fat than women of the same weight. Muscle tissue burns more calories at rest than fat tissue, resulting in higher BMR.
Yes. BMR decreases with age — roughly 1–2% per decade after age 20. This is why it becomes harder to maintain weight as you age.
Yes! Building muscle through strength training is the most effective way to permanently increase BMR. Each kg of muscle burns ~13 kcal at rest vs ~4.5 kcal for fat.
BMR = calories at complete rest. RMR (Resting Metabolic Rate) ≈ BMR + minimal daily movement (~10% higher). TDEE = RMR × activity factor = total daily calories burned.