What is TDEE?
Your Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a 24-hour period. It includes everything: your resting metabolism, the energy cost of digestion, and the calories burned during physical activity.
Most people only think about calories burned during exercise — but this is typically just 20–30% of your total daily burn. The majority comes from your Basal Metabolic Rate (BMR), the energy your body needs just to stay alive: breathing, circulation, cell repair, and organ function.
How is TDEE calculated?
This calculator uses the Mifflin-St Jeor equation — the most validated formula for estimating BMR in modern research — then multiplies by an activity factor to give your TDEE.
For men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
For women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
Your BMR is then multiplied by your activity level (1.2 to 1.9) to produce your TDEE.
Why does your TDEE matter?
Knowing your TDEE is the single most important number for managing your body composition. If you eat below it consistently, you lose weight. If you eat above it, you gain. If you match it, you maintain. Without knowing this number, you're guessing — and most people guess wrong by hundreds of calories a day.
Frequently asked questions
How accurate is this TDEE calculator?
The Mifflin-St Jeor equation is accurate to within 10% for most people. The bigger source of error is usually the activity multiplier — people tend to overestimate how active they are. If your results aren't matching reality after a few weeks, try dropping one activity level down.
Should I eat exactly my TDEE every day?
Your TDEE is an average, not a daily prescription. It's perfectly normal — and arguably better — to vary your intake day to day while keeping your weekly average near your target. This is sometimes called calorie cycling.
Does TDEE change over time?
Yes. As you lose or gain weight, your TDEE changes — lighter bodies burn fewer calories. Recalculate every 4–6 weeks, or any time your weight changes by more than 5kg, to keep your targets accurate.
What's the difference between TDEE and BMR?
BMR (Basal Metabolic Rate) is what you'd burn lying completely still all day — your body's minimum energy requirement. TDEE is your BMR multiplied by your activity level, giving a realistic picture of your actual daily calorie burn including movement, exercise, and digestion.
How fast should I aim to lose weight?
A deficit of 500 kcal/day produces roughly 0.5kg (1lb) of fat loss per week — a widely recommended sustainable rate. Deficits above 1000 kcal/day risk muscle loss, fatigue, and metabolic adaptation. Slow and steady produces better long-term results.
Disclaimer: This calculator provides estimates based on established nutritional science formulas. Results are for informational purposes only and are not a substitute for personalised advice from a registered dietitian or medical professional. Individual metabolism varies. Always consult a qualified health professional before making significant changes to your diet or exercise routine.