How this TDEE calculator works
Your Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a day. It combines the energy you use at complete rest with the energy spent digesting food, moving around and exercising. Eating roughly your TDEE keeps your weight stable; eating below it leads to weight loss, and above it to weight gain.
The calculation has two steps. First, this tool estimates your Basal Metabolic Rate (BMR) — the calories you burn at rest — using the Mifflin-St Jeor equation, widely regarded as one of the most accurate general formulas. For men, BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5; for women the final constant is −161 instead of +5. Second, your BMR is multiplied by an activity factor from 1.2 (sedentary) to 1.9 (extra active) to give your TDEE.
Reference note: imperial inputs are converted to metric before the formula runs — pounds are multiplied by 0.453592 to get kilograms, and total height in inches is multiplied by 2.54 to get centimetres. Results are rounded to whole calories.
Activity levels at a glance
Pick the multiplier that best matches a typical week:
| Activity level | Factor |
|---|---|
| Sedentary — little or no exercise, desk job | 1.2 |
| Lightly active — light exercise 1–3 days/week | 1.375 |
| Moderately active — moderate exercise 3–5 days/week | 1.55 |
| Very active — hard exercise 6–7 days/week | 1.725 |
| Extra active — very hard exercise or physical job | 1.9 |
Frequently asked questions
- What is TDEE?
- TDEE stands for Total Daily Energy Expenditure — the total calories your body burns in a day, including your resting metabolism plus everything you do, from digesting food to walking and exercising. It is roughly the number of calories you need to maintain your current weight.
- How is TDEE calculated?
- First your BMR is estimated with the Mifflin-St Jeor equation from your sex, age, height and weight. TDEE is then your BMR multiplied by an activity factor between 1.2 (sedentary) and 1.9 (extra active) that reflects how much you move during a typical day.
- What is BMR?
- BMR, or Basal Metabolic Rate, is the calories your body burns at complete rest just to keep you alive — powering your heart, brain, breathing and other basic functions. It is the largest part of your daily calorie burn and the starting point for your TDEE.
- How many calories should I eat to lose weight?
- Weight loss requires eating fewer calories than your TDEE. A moderate deficit of 250 to 500 calories per day generally leads to slow, sustainable loss of about 0.25 to 0.5 kg (0.5 to 1 lb) per week. The targets table above shows those numbers for you.
- What activity level should I pick?
- Choose the level matching a typical week: sedentary (1.2) for a desk job with little exercise, lightly active (1.375) for light exercise 1–3 days, moderately active (1.55) for 3–5 days, very active (1.725) for hard exercise 6–7 days, and extra active (1.9) for very hard exercise or a physical job. When unsure, pick the lower option.
- Is this TDEE calculator accurate?
- The Mifflin-St Jeor equation is one of the most accurate general formulas, but every result is an estimate. Real needs vary with body composition, genetics and habits, so use the number as a starting point, track your weight over a few weeks and adjust based on what actually happens.
- These figures are general fitness estimates, not medical or nutritional advice. For a plan tailored to your health, consult a qualified professional.