TDEE Calculator
Enter your sex, age, height, weight, and activity level to find your Total Daily Energy Expenditure (TDEE): the number of calories your body needs each day to maintain your current weight. You also get your Basal Metabolic Rate (BMR), an adjustable calorie goal for cutting or bulking, and a macronutrient breakdown. Switch between metric and imperial units instantly. If you know your body-fat percentage, select Katch-McArdle for a more accurate estimate.
Formula
Worked example
A 30-year-old male weighing 75 kg and standing 175 cm, moderately active: BMR = 10(75) + 6.25(175) - 5(30) + 5 = 750 + 1093.75 - 150 + 5 = 1698.75 kcal/day. TDEE = 1699 x 1.55 = 2633 kcal/day. On a 500 kcal/day deficit (goal = cut), his target is 2133 kcal/day, implying roughly 0.45 kg (1 lb) of fat loss per week.
What is TDEE and why does it matter?
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a day, covering everything from breathing and organ function at rest all the way through to digestion and physical activity. It is the number that determines whether you lose, maintain, or gain weight: eat below it consistently and you lose fat; eat above it and you gain. Because TDEE varies widely by age, sex, body size and activity level, an accurate personal estimate is the foundation of any evidence-based nutrition plan.
How this calculator works
The calculator first estimates your Basal Metabolic Rate (BMR), the calories you would burn lying still for 24 hours, using either the Mifflin-St Jeor equation (the standard for most people) or the Katch-McArdle equation if you enter your body-fat percentage. BMR is then multiplied by a Physical Activity Level (PAL) factor that accounts for how much you move each day, producing your TDEE. From there you choose a goal: a calorie deficit for fat loss, maintenance, or a surplus for muscle gain. The macro targets are calculated from your goal calories using evidence-based protein, carbohydrate, and fat splits tuned for each goal. The 12-week projection chart shows the expected weight trajectory at your chosen deficit or surplus, assuming no adaptation.
Mifflin-St Jeor vs Katch-McArdle: which formula should you use?
The Mifflin-St Jeor equation (published 1990) is widely considered the most accurate BMR formula for the general population and is the default in clinical practice. It uses weight, height, age and sex. The Katch-McArdle equation (1975) skips height and sex entirely and instead works from lean body mass, making it more accurate for people who know their body-fat percentage with confidence, particularly athletes and those with unusually high or low body-fat levels. If you do not have a reliable body-fat measurement from DEXA, underwater weighing, or a validated skinfold protocol, stick with Mifflin-St Jeor.
Setting a calorie target and macros
A deficit of 500 kcal/day produces approximately 0.5 kg (about 1 lb) of fat loss per week, as 1 kg of fat stores roughly 7,700 kcal. A 250 kcal deficit is gentler and better tolerated long-term; a 1,000 kcal deficit is aggressive and risks muscle loss and fatigue unless protein is kept very high and training is maintained. Protein is prioritised on cuts at 35-45% of calories (about 1.6-2.2 g per kg of bodyweight) to preserve lean mass. Carbohydrates fuel training and recovery, while dietary fat supports hormonal health and is never cut below about 20% of total calories. During a bulk, the calorie surplus should be modest (250-500 kcal) to limit fat gain alongside muscle growth.
Activity level multipliers (PAL)
| Activity level | Description | PAL multiplier |
|---|---|---|
| Sedentary | Desk job, little or no exercise | 1.2 |
| Lightly active | Light exercise 1-3 days per week | 1.375 |
| Moderately active | Moderate exercise 3-5 days per week | 1.55 |
| Very active | Hard exercise 6-7 days per week | 1.725 |
| Extra active | Hard daily exercise plus physical job | 1.9 |
| Professional | Elite athlete or twice-daily training | 2.4 |
Harris-Benedict and Mifflin-St Jeor both use these standard physical activity level factors.
Frequently asked questions
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the energy your body uses at complete rest, just to keep you alive: heartbeat, breathing, temperature regulation and organ function. TDEE adds the thermic effect of food (roughly 10% of calories eaten) and all physical activity on top of BMR. For most people, TDEE is 20-100% higher than BMR depending on activity level.
How accurate is a TDEE calculator?
Population-based equations like Mifflin-St Jeor typically estimate TDEE within 10-15% for most individuals. The biggest source of error is the activity multiplier, which people tend to overestimate. Tracking your actual food intake and body weight for two to four weeks, then adjusting calories by 100-200 kcal if weight is not trending as expected, is more reliable than any single formula.
How much of a calorie deficit is safe for fat loss?
A deficit of 250-500 kcal/day is considered moderate and safe for most healthy adults, producing 0.25-0.5 kg (0.5-1 lb) of fat loss per week. Deficits above 1,000 kcal/day increase the risk of muscle loss, nutrient deficiencies and metabolic adaptation. Aggressive deficits should only be used under medical supervision.
Why does the Katch-McArdle formula require body fat?
Katch-McArdle calculates BMR from lean body mass (total mass minus fat mass) rather than total weight. Fat tissue is metabolically less active than muscle, so two people with the same weight but different body compositions burn different amounts at rest. If you know your body-fat percentage from a reliable source, Katch-McArdle gives a more personalized BMR estimate.
Will my TDEE change if I lose or gain weight?
Yes. As you lose weight your BMR falls because there is less tissue to maintain, and your TDEE decreases accordingly. This is called metabolic adaptation and is why calorie targets need to be recalculated every few weeks during an active cut or bulk. Resistance training helps counteract adaptation by preserving muscle mass.
How do I choose the right activity level?
Most people overestimate their activity level. "Moderately active" (PAL 1.55) fits someone who exercises three to five times a week at genuine moderate intensity and has a non-physical job. If you sit at a desk most of the day and exercise two to three times a week, "lightly active" (PAL 1.375) is usually more accurate. When in doubt, choose the lower option and adjust upward if your weight is dropping faster than expected.