BMR & TDEE Calculator

Understanding BMR and TDEE

Your metabolism determines how many calories you burn each day. BMR and TDEE are the two key numbers for weight management, whether you're trying to lose, gain, or maintain your weight.

What is BMR?

Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest just to stay alive - breathing, circulating blood, regulating temperature, and growing cells.

Key Point: This is the minimum calories you need even if you did absolutely nothing all day.

What is TDEE?

Total Daily Energy Expenditure (TDEE) is your BMR plus all the calories you burn through daily activities and exercise.

TDEE = BMR × Activity Multiplier

Activity Levels:

• Sedentary (little to no 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/physical job): BMR × 1.9

Using These Numbers

To Lose Weight: Eat 500 calories below TDEE

• Creates a 1 lb/week fat loss (3,500 calorie deficit per week)
• Safe, sustainable rate

To Gain Weight: Eat 300-500 calories above TDEE

• Supports muscle growth with training
• Minimizes fat gain

To Maintain: Eat at your TDEE

• Maintain current weight
• Support performance

Factors Affecting BMR

Your BMR depends on:

Age: Decreases ~2% per decade after 30

Sex: Men typically have 5-10% higher BMR

Weight: Larger bodies burn more calories

Height: Taller people have higher BMR

Muscle Mass: Muscle burns more than fat (even at rest!)

Genetics: Can vary 20-30% between individuals

Common Mistakes

Eating Below BMR

• Severely damages metabolism
• Causes muscle loss
• Triggers extreme hunger
• Unsustainable long-term
• Minimum: Never go below 1,200 (women) or 1,500 (men) calories

Overestimating Activity

• Most people are "lightly active" at best
• Exercise burns less than you think
• Start conservative, adjust based on results

Ignoring Body Composition

• Two people, same weight, different muscle
• More muscle = higher BMR
• Focus on body composition, not just scale

Boosting Your Metabolism

Build Muscle:

• Each pound of muscle burns 6 calories/day at rest
• Strength training 2-3×/week

Stay Active:

• 10,000 steps/day baseline
• NEAT (Non-Exercise Activity) matters
• Take stairs, stand more, fidget!

Eat Enough Protein:

• 0.7-1g per pound of body weight
• Higher thermic effect than carbs/fat
• Preserves muscle during weight loss

Don't Crash Diet:

• Moderate deficits preserve metabolism
• Include diet breaks every 8-12 weeks
• Reverse diet when returning to maintenance

Tracking Progress

First 2-3 weeks: Track weight and adjust calories

Weight going down too fast (>2 lbs/week): Eat more

No change after 2 weeks: Reduce by 200 calories

Gaining unintentionally: Reduce by 200-300 calories

Best Practice: Weigh daily, compare weekly averages

The 80/20 Rule

80% of results come from:

• Eating the right total calories
• Getting adequate protein
• Consistent training
• Quality sleep (7-9 hours)

20% of results come from:

• Meal timing
• Supplement timing
• Specific macronutrient ratios
• Advanced techniques

Focus on the fundamentals first!

Use this calculator to find your personalized calorie targets and take control of your body composition goals.