GoToolGo

🔥 TDEE & BMR Calculator

Find exactly how many calories your body burns per day, using the same Mifflin-St Jeor formula nutritionists and trainers actually use.

Your Results

0 calories/day
BMR (calories at total rest): 0
GoalDaily CaloriesApprox. Weekly Change
Aggressive Fat Loss0~2 lb/week
Moderate Fat Loss0~1 lb/week
Maintenance00 lb/week
Lean Muscle Gain0~0.5 lb/week

💪 Now Split That Into Macros

Knowing your calorie target is step one. Our Macro Calculator turns that number into exact grams of protein, carbs, and fat for your goal — including a dedicated keto mode.

Calculate My Macros 🚀

BMR vs. TDEE: What's the Difference?

BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest — just keeping your heart beating, lungs breathing, and brain functioning. It's the absolute minimum.

TDEE (Total Daily Energy Expenditure) is your BMR plus everything else you do in a day: walking, working, exercising, even fidgeting. TDEE is the number that actually matters for setting a calorie target, since it reflects your real day-to-day life, not a hypothetical day in bed.

Why We Use the Mifflin-St Jeor Formula

There are several BMR formulas (Harris-Benedict, Katch-McArdle, Mifflin-St Jeor). We use Mifflin-St Jeor because independent validation studies have repeatedly found it to be the most accurate for the general population, typically within 10% of measured metabolic rate. Older formulas like Harris-Benedict tend to overestimate calorie needs by a meaningful margin.

How to Pick Your Activity Level Honestly

This is where most people get their number wrong — not from the formula, but from overestimating their own activity level. "Moderately Active" means structured exercise 3-5 days a week on top of a normal daily routine, not just "I walk around the office sometimes." If you're unsure, round down — it's easier to add calories back if you're losing weight too fast than to fix months of eating above your real maintenance.

Frequently Asked Questions

How accurate is a TDEE calculator?

Formula-based TDEE estimates are typically accurate within 10-15% for most people, which is a solid starting point — but they're an estimate, not a measurement. Track your actual weight trend over 2-3 weeks at your calculated intake and adjust by 100-200 calories if you're not seeing the expected result.

Should I eat back the calories I burn from exercise?

No, not if your activity level already accounts for it. Your activity level multiplier already factors in typical exercise for that category. Adding back exercise calories on top of an "Active" or "Very Active" selection usually double-counts the same calories.

Why did my TDEE go down even though I didn't change anything?

As you lose weight, your BMR decreases too, since a smaller body requires less energy to maintain. This is normal and expected — recalculate your TDEE every 10-15 lbs of weight change, not just once at the start. Still fuzzy on the difference between the two numbers this tool gives you? Read our plain-English guide to TDEE vs BMR.

TDEE Resources & Related Calculators

Deepen your understanding of energy expenditure with these guides and tools: