BMR Calculator
Daily Calories by Activity Level
BMR Ranges by Age & Sex
Approximate BMR ranges for average-height adults at healthy weight
| Age Range | Men (cal/day) | Women (cal/day) |
|---|---|---|
| 18-25 | 1,700-1,900 | 1,400-1,600 |
| 26-35 | 1,600-1,800 | 1,350-1,550 |
| 36-45 | 1,550-1,750 | 1,300-1,500 |
| 46-55 | 1,500-1,700 | 1,250-1,450 |
| 56-65 | 1,400-1,600 | 1,200-1,400 |
| 66-75 | 1,350-1,550 | 1,150-1,350 |
| 76+ | 1,250-1,450 | 1,100-1,300 |
How We Calculate This
This bmr calculator uses established formulas and industry-standard data to provide accurate estimates.
- Enter your specific values into the calculator fields above
- Our algorithm applies the relevant formulas using your inputs
- Results are calculated instantly in your browser — nothing is sent to a server
- Review the detailed breakdown to understand how each factor affects your result
These calculations are estimates based on standard formulas. For critical decisions, always consult a qualified professional.
How to Convert Oven Recipes to Air Fryer
The BMR calculator uses the Mifflin-St Jeor equation, considered the most accurate formula for estimating basal metabolic rate.
The basic rule:
- Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
- Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
- BMR represents the calories your body burns at complete rest — just to maintain basic life functions
- Multiply BMR by an activity factor (1.2–1.9) to estimate total daily energy expenditure (TDEE)
Your BMR accounts for about 60-75% of your total daily calorie burn. The remaining comes from physical activity (15-30%) and the thermic effect of food (about 10%).
When Would You Use This Calculator?
This bmr calculator is designed for anyone who needs quick, reliable estimates without complex spreadsheets or professional consultations.
- When you need a quick estimate before committing to a purchase or project
- When comparing different options or scenarios side by side
- When planning a budget and need to understand potential costs
- When you want to verify a quote or estimate you've received from a professional
- When teaching or learning about the concepts behind these calculations
Frequently Asked Questions
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the calories your body burns at complete rest — just breathing, circulating blood, and maintaining organs. TDEE (Total Daily Energy Expenditure) includes BMR plus calories burned through physical activity and digestion.
Why is Mifflin-St Jeor more accurate than Harris-Benedict?
The Mifflin-St Jeor equation was developed in 1990 using modern data and has been shown in multiple studies to predict BMR within 10% for most people. The older Harris-Benedict equation (1919) tends to overestimate BMR, especially for overweight individuals.
How can I use BMR for weight loss?
To lose weight, you need to eat fewer calories than your TDEE (BMR × activity factor). A deficit of 500 calories per day leads to about 1 lb of weight loss per week. Never eat below your BMR, as this can slow your metabolism and be unhealthy.
Does muscle mass affect BMR?
Yes, muscle tissue burns more calories at rest than fat tissue. Each pound of muscle burns about 6 calories per day at rest, compared to 2 calories per pound of fat. This is why strength training can increase your BMR over time.
Does BMR change with age?
Yes, BMR decreases by about 1-2% per decade after age 20, primarily due to loss of muscle mass and hormonal changes. This is why maintaining muscle through strength training becomes increasingly important with age.
What activity multipliers should I use?
Sedentary (desk job, little exercise): BMR × 1.2. Lightly active (1-3 days/week): BMR × 1.375. Moderately active (3-5 days/week): BMR × 1.55. Very active (6-7 days/week): BMR × 1.725. Extremely active (athlete): BMR × 1.9.