TDEE Calculator
The average adult burns between 1,600 and 3,000 calories per day depending on age, gender, weight, and activity level. Your Total Daily Energy Expenditure (TDEE) is the exact number of calories your body burns daily, including your resting metabolism, physical activity, and digestion. Enter your details below to calculate yours in seconds using the Mifflin-St Jeor equation.
The Mifflin-St Jeor Equation
This calculator uses the Mifflin-St Jeor equation, developed in 1990 by a team of researchers led by MD Mifflin and ST St Jeor. It is the formula recommended by the Academy of Nutrition and Dietetics because it is the most accurate predictive equation for estimating BMR in healthy adults, typically within 10% of lab-measured values.
BMR Formulas
Men: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) + 5
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) - 161
What Each Variable Means
- Weight (kg): Your body weight converted to kilograms. Heavier bodies require more energy to maintain basic functions, so weight has the largest coefficient in the equation.
- Height (cm): Your height converted to centimeters. Taller people have a larger body surface area and more tissue to maintain, which increases calorie needs.
- Age (years): As you age, you tend to lose muscle mass and your metabolic rate gradually decreases. The equation subtracts 5 calories for each year of age.
- Gender constant (+5 or -161): Men typically have more lean mass than women at the same height and weight, which results in a higher BMR. The +5 for men and -161 for women accounts for this average difference.
Activity Multipliers
Your BMR only accounts for calories burned at complete rest. To estimate your total daily burn, the calculator multiplies your BMR by an activity factor. These multipliers come from the Harris-Benedict activity scale, which has been validated across decades of research.
| Activity Level | Multiplier |
|---|---|
| Sedentary | 1.2 |
| Lightly Active | 1.375 |
| Moderately Active | 1.55 |
| Very Active | 1.725 |
| Extra Active | 1.9 |
If you are unsure which level to choose, pick one level lower than you think. Most people overestimate how active they are.
Worked Examples
Here are three step-by-step calculations for different body types so you can see exactly how the math works.
Example 1: Sedentary Office Worker
30-year-old female, 5'5" (165.1 cm), 140 lbs (63.5 kg), sedentary activity level.
Step 1: Convert units
140 lbs × 0.4536 = 63.5 kg
(5 × 12 + 5) × 2.54 = 165.1 cm
Step 2: Calculate BMR (female formula)
(10 × 63.5) + (6.25 × 165.1) - (5 × 30) - 161
= 635.0 + 1,031.9 - 150 - 161
= 1,356 calories/day (BMR)
Step 3: Multiply by activity factor (sedentary = 1.2)
1,356 × 1.2
= 1,627 calories/day (TDEE)
Example 2: Active Gym-Goer
28-year-old male, 5'10" (177.8 cm), 180 lbs (81.6 kg), moderately active.
Step 1: Convert units
180 lbs × 0.4536 = 81.6 kg
(5 × 12 + 10) × 2.54 = 177.8 cm
Step 2: Calculate BMR (male formula)
(10 × 81.6) + (6.25 × 177.8) - (5 × 28) + 5
= 816.5 + 1,111.3 - 140 + 5
= 1,793 calories/day (BMR)
Step 3: Multiply by activity factor (moderately active = 1.55)
1,793 × 1.55
= 2,779 calories/day (TDEE)
Example 3: Older Adult Trying to Lose Weight
55-year-old female, 5'4" (162.6 cm), 170 lbs (77.1 kg), lightly active.
Step 1: Convert units
170 lbs × 0.4536 = 77.1 kg
(5 × 12 + 4) × 2.54 = 162.6 cm
Step 2: Calculate BMR (female formula)
(10 × 77.1) + (6.25 × 162.6) - (5 × 55) - 161
= 771.1 + 1,016.0 - 275 - 161
= 1,351 calories/day (BMR)
Step 3: Multiply by activity factor (lightly active = 1.375)
1,351 × 1.375
= 1,858 calories/day (TDEE)
Notice how age reduces BMR significantly. At 55, this person's BMR is similar to the 30-year-old in Example 1 despite weighing 30 pounds more. This is why recalculating as you age matters.
What to Do With Your TDEE
Your TDEE is a starting point, not a final answer. Here is how to use it depending on your goal.
Weight Loss
Eat 300-500 calories below your TDEE. A 500-calorie daily deficit produces roughly 1 pound of fat loss per week. A 300-calorie deficit is slower but easier to maintain long term.
Do not go below 1,200 calories per day without guidance from a doctor or dietitian. Very low calorie diets can slow your metabolism and cause muscle loss.
Maintenance
Eat right at your TDEE. This is the number of calories needed to keep your current weight stable. In practice, your weight will still fluctuate 2-5 pounds day to day from water, sodium, and digestion.
Maintenance is a useful phase after a long diet to let your body and metabolism recover before starting another deficit.
Muscle Gain
Eat 200-300 calories above your TDEE. A moderate surplus gives your body the extra energy it needs to build new muscle tissue without excessive fat gain.
Combine this surplus with a strength training program and adequate protein (0.7-1g per pound of body weight) for best results.
When to Recalculate Your TDEE
- Every 10-15 pounds of weight change. As your weight changes, your BMR changes with it. A person who loses 20 pounds may need 100-200 fewer calories per day than before.
- When your activity level changes. Starting or stopping an exercise program, changing jobs, or recovering from an injury all affect your daily burn.
- When your progress stalls. If your weight has not moved in 2-3 weeks and you are confident in your tracking, recalculate and adjust your target.
- Every few months as a routine check. Even if things are going well, recalculating quarterly helps you stay ahead of plateaus.
Want to Go Deeper?
We have written detailed guides that cover TDEE, BMR, calorie deficits, and related topics:
- How to Calculate Your TDEE: A Simple Guide to Total Daily Energy ExpenditureA full walkthrough of TDEE calculation, how to interpret your number, and how to adjust over time.
- What Is BMR and How Do You Calculate It?Everything you need to know about your Basal Metabolic Rate and why it accounts for 60-75% of your daily calorie burn.
- What Is a Calorie Deficit and How Does It Actually Work?How to set up a sustainable deficit using your TDEE, with practical tips to avoid common mistakes.
- Is 1500 Calories a Day Enough to Lose Weight?Understand how 1,500 calories compares to different TDEE levels and when it is or is not a good target.