BMR / TDEE Calculator

What is TDEE?

TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in a day, combining your basal metabolic rate (BMR) with the energy used for physical activity and digestion. Knowing your TDEE helps you manage weight: eat fewer calories to lose weight, more to gain, or match it to maintain.

TDEE is composed of three parts: BMR (60-70% of TDEE, energy for basic life functions), the thermic effect of food (about 10%, energy to digest and absorb food), and physical activity (20-30%, the most variable component). The activity level multiplier accounts for exercise and daily movement patterns.

How to use this tool

Enter your age, gender, weight, height, and activity level. The tool calculates your BMR using established formulas (Mifflin-St Jeor or Harris-Benedict) and multiplies by an activity factor to estimate your TDEE. Results show daily calorie targets for maintenance, weight loss (deficit), and weight gain (surplus).

Activity level multipliers

• Sedentary (office job, little exercise): BMR x 1.2.
• Lightly active (light exercise 1-3 days/week): BMR x 1.375.
• Moderately active (moderate exercise 3-5 days/week): BMR x 1.55.
• Very active (hard exercise 6-7 days/week): BMR x 1.725.
• Extremely active (physical job + hard exercise): BMR x 1.9.

Using TDEE for weight management

To lose weight, eat 300-500 calories below your TDEE (a moderate deficit that preserves muscle mass). To gain weight, eat 250-500 calories above TDEE. A 500-calorie daily deficit equals approximately 0.45 kg (1 pound) of weight loss per week. Extreme deficits (over 1,000 calories below TDEE) are unsustainable and can cause muscle loss, metabolic slowdown, and nutritional deficiencies.

Frequently asked questions

How accurate is a TDEE calculator?

TDEE calculations are estimates, typically within 10-15% of actual expenditure. Individual variations in metabolism, body composition, NEAT (non-exercise activity thermogenesis like fidgeting), and genetics can cause significant differences. Use the calculated TDEE as a starting point, then adjust based on real-world results over 2-4 weeks.

What is the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the calories your body burns at complete rest — just to keep vital organs functioning (breathing, circulation, cell production). TDEE includes BMR plus all additional energy expenditure from physical activity, digestion, and daily movement. BMR is typically 60-70% of TDEE. You should never eat below your BMR.