TDEE Calculator

TDEE Calculator | Sixpacks.fit

TDEE Calculator

Estimate how many calories your body burns each day. This TDEE calculator uses the Mifflin-St Jeor equation to compute your maintenance calories, BMR, and energy expenditure across all five activity levels.

Mifflin-St Jeor 5 Activity Levels Range-Based Results
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Your Stats

Enter your details to estimate your daily energy expenditure
Free and Private
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If provided, the calculator uses the Katch-McArdle formula, which is more accurate for lean individuals. Need help? Try our Body Fat Calculator.
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All five TDEE values are shown in results regardless of your selection.
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Energy Expenditure Report

Personalized metabolic estimate
Mifflin-St Jeor
Estimated Maintenance Calories
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Likely range: 0 to 0 kcal/day
Based on your selected activity level
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BMR (at rest)
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TDEE (selected)
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Daily Water (L)
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BMI
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Where Your Daily Energy Goes

BMR 0%
NEAT 0%
TEF 0%
EAT 0%

BMR is your resting metabolism. NEAT is non-exercise movement. TEF is the energy used digesting food. EAT is structured exercise. These proportions are estimates and vary by individual.

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TDEE at Every Activity Level

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Your BMI--
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Healthy range18.5 to 24.9
UnderNormalOverObese

infoAbout This Estimate

FormulaMifflin-St Jeor
Accuracy+/- 10%
Low estimate--
High estimate--
trending_downPlan a Deficit

What Is TDEE?

TDEE stands for Total Daily Energy Expenditure. It is an estimate of the total number of calories your body burns in a 24-hour period when you account for everything: keeping your organs functioning, digesting food, moving around, and exercising. It is the starting point for understanding your nutrition needs, whether your goal is fat loss, muscle gain, or weight maintenance.

Think of TDEE as your body's daily energy budget. Every calorie you eat above this number gets stored (as fat or muscle). Every calorie below it comes from stored energy (primarily body fat). Knowing your TDEE turns nutrition from a guessing game into a measurable, adjustable system.

BMR vs TDEE: What Is the Difference?

These two terms are often confused, and the confusion causes real problems. Your BMR (Basal Metabolic Rate) is what your body burns at complete rest, just keeping your heart beating, lungs breathing, and cells repairing. For most adults, BMR is between 1,400 and 1,800 calories per day.

Your TDEE is your BMR multiplied by an activity factor that reflects how much you move. For most adults, TDEE ranges from 2,000 to 3,500 calories. The gap between BMR and TDEE is your "activity budget," the calories you burn through daily movement and exercise.

Eating below your BMR for extended periods can slow your metabolism and cause muscle loss. Eating below your TDEE (but above your BMR) is what a healthy, sustainable calorie deficit looks like. If you want to plan a deficit, use the Calorie Deficit Calculator.

How Your TDEE Is Estimated

This calculator runs two steps. First, it estimates your BMR using a predictive equation. Then it multiplies your BMR by an activity factor to produce your TDEE.

The Mifflin-St Jeor Equation

By default, the calculator uses the Mifflin-St Jeor equation, developed in the 1990s and widely considered the most accurate predictive formula for healthy adults:

  • Men: BMR = (10 x weight in kg) + (6.25 x height in cm) minus (5 x age) + 5
  • Women: BMR = (10 x weight in kg) + (6.25 x height in cm) minus (5 x age) minus 161

The Katch-McArdle Alternative

If you enter your body fat percentage, the calculator switches to the Katch-McArdle formula: BMR = 370 + (21.6 x lean body mass in kg). This formula is more accurate for lean individuals and athletes because it accounts for the fact that muscle tissue burns more calories at rest than fat tissue. If you do not know your body fat percentage, you can estimate it using our Body Fat Calculator.

infoWhy This Calculator Shows a Range

No predictive formula can measure your actual metabolism. The Mifflin-St Jeor equation is accurate within approximately plus or minus 10 percent. That means if your calculated TDEE is 2,500, your true maintenance could be anywhere from 2,250 to 2,750. This is why we show a range rather than a single precise-looking number.

Choosing Your Activity Level

Your activity factor reflects your total daily movement, not just your workouts. This is where most people overestimate. Be honest: overestimating by one tier adds 200 to 400 calories to your TDEE and can completely derail your nutrition plan.

LevelMultiplierTypical Day
Sedentary1.2Desk job, no exercise, under 3,000 daily steps
Lightly Active1.3751 to 3 light workouts per week, or 5,000 to 7,000 daily steps
Moderately Active1.553 to 5 structured workouts per week, or 7,000 to 10,000 daily steps
Very Active1.7256 to 7 hard workouts per week, or physical job
Athlete1.9Two-a-day training, or manual labor plus gym

If you are unsure between two levels, choose the lower one. It is better to underestimate slightly and adjust upward based on real data than to overestimate and wonder why the scale is not moving.

How to Interpret Your TDEE

Your TDEE is an estimate of the calories you would need to eat to maintain your current weight at your current activity level. It is not a prescription, and it is not exact.

If you eat at your TDEE, your weight should remain roughly stable over time (ignoring normal daily fluctuations of 1 to 3 pounds from water, glycogen, and digestive contents). If you eat below your TDEE, you will lose weight. If you eat above it, you will gain weight.

The result shown is a single estimate. The range below and above it represents the likely window where your true maintenance lies. Start with the middle number and adjust based on what actually happens to your weight over 2 to 3 weeks.

Why Your Actual Calorie Needs May Differ

Several factors affect your true energy expenditure that no formula can capture:

  • NEAT (Non-Exercise Activity Thermogenesis): The calories you burn from fidgeting, walking, standing, and gesturing. NEAT varies by up to 2,000 calories per day between individuals and is the single biggest reason two people with identical stats can have very different maintenance levels.
  • Sleep quality: Poor sleep can reduce your daily energy expenditure by 100 to 200 calories through fatigue and metabolic slowdown.
  • Body composition: Muscle burns roughly 6 calories per pound per day at rest. Fat burns about 2. Adding 10 pounds of muscle raises your BMR by about 60 calories per day.
  • Hormones: Thyroid function, cortisol levels, and insulin sensitivity all influence metabolic rate.
  • Metabolic adaptation: After 8 to 12 weeks of eating in a deficit, your metabolism can slow by 5 to 15 percent below what any formula predicts.
  • Age: Metabolic rate declines 1 to 2 percent per decade after 30, mostly due to muscle loss. Resistance training largely eliminates this decline.

How to Refine Your Maintenance Estimate

The calculator gives you a starting point. To find your true maintenance, you need to test it against reality:

  1. Eat at your calculated TDEE for 2 weeks. Track your calorie intake honestly, including cooking oils, condiments, and weekend meals.
  2. Weigh yourself every morning after using the bathroom, before eating or drinking. Take a weekly average.
  3. If your weight is stable (within 0.5 pounds), your TDEE estimate is close to accurate.
  4. If your weight drops by more than 1 pound per week, your true TDEE is higher than calculated. Add 150 calories and retest.
  5. If your weight rises by more than 1 pound per week, your true TDEE is lower than calculated. Subtract 150 calories and retest.

Remember that body weight fluctuates daily due to water retention, glycogen, sodium, digestive contents, and hormonal changes. A single day's weight means very little. Weekly averages are what matter.

Recalculate your TDEE every 4 to 6 weeks during a cut or bulk, or whenever your weight changes by 5 pounds or more. As your body changes, so does your energy expenditure.

When to Use a Different Calculator

This TDEE Calculator is designed to help you understand your daily energy expenditure and maintenance calories. Other Sixpacks.fit tools serve different purposes:

  • Calorie Deficit Calculator: If your goal is fat loss, use this tool. It takes your TDEE and helps you choose a deficit size, set a target calorie intake, and estimate a timeline for reaching your goal weight.
  • Macro Calculator: If you want to break your calorie target into protein, carbohydrates, and fat, use this tool. It provides personalized macro targets based on your goals.
  • Six Pack Timeline Calculator: If you want to know how long it might take to reach visible abs, use this tool. It factors in your current body fat and target body fat to estimate a timeline.

TDEE Calculator FAQs

TDEE stands for Total Daily Energy Expenditure. It is an estimate of the total number of calories your body burns in a 24-hour period, including all activity. It is calculated by multiplying your Basal Metabolic Rate (BMR) by an activity factor that reflects your typical daily movement.
BMR stands for Basal Metabolic Rate. It is the estimated number of calories your body would burn if you stayed in bed all day doing nothing but keeping your organs alive. BMR typically accounts for 60 to 70 percent of your total daily energy expenditure.
BMR is what you burn at complete rest. TDEE is your BMR multiplied by your activity level. BMR is typically 1,400 to 1,800 calories for most adults, while TDEE is typically 2,000 to 3,500 calories depending on how active you are.
This calculator uses the Mifflin-St Jeor equation to estimate BMR, then multiplies it by an activity factor (1.2 for sedentary through 1.9 for athlete). If you provide your body fat percentage, it switches to the Katch-McArdle formula, which uses lean body mass instead of total body weight.
Choose the level that best matches your typical week, not your best day. If you train hard 4 times per week but sit at a desk for 9 hours and walk fewer than 5,000 steps, you are likely Lightly Active, not Very Active. Overestimating is the most common cause of inaccurate TDEE results.
The Mifflin-St Jeor equation is accurate within approximately plus or minus 10 percent for healthy adults. Your actual maintenance could be 200 to 300 calories higher or lower than the estimate. Use the result as a starting point and refine it by tracking your weight trend over 2 to 3 weeks.
In practice, yes. TDEE represents your estimated daily energy expenditure, which is the number of calories you would need to eat to maintain your current weight at your current activity level. Maintenance calories is simply TDEE expressed as an intake target rather than an expenditure estimate.
Several factors the formula cannot capture: NEAT (daily fidgeting and movement) varies by up to 2,000 calories between individuals, sleep quality affects metabolic rate, body composition influences calorie burn at rest, hormones play a role, and metabolic adaptation after prolonged dieting can lower your actual TDEE by 5 to 15 percent.
You can use your TDEE as a daily target, but daily calorie intake naturally varies. What matters is the weekly and monthly average. If your TDEE is 2,500, eating between 2,300 and 2,700 on most days will produce roughly the same maintenance effect over time.
Yes. As you lose weight, your BMR decreases because a smaller body requires less energy. Expect your TDEE to drop by 100 to 200 calories for every 10 pounds of weight lost. Recalculate your TDEE every 4 to 6 weeks during a cut or bulk.
Recalculate every 4 to 6 weeks during a cut or bulk, or whenever your weight changes by 5 pounds or more. Also recalculate if you significantly change your activity level, such as starting a new training program or switching from a desk job to an active one.
Use the Sixpacks.fit Calorie Deficit Calculator. It takes your TDEE as a starting point and helps you choose a deficit size, set macro targets, and estimate a timeline for reaching your goal weight. The TDEE Calculator on this page is designed for understanding your energy expenditure; the Calorie Deficit Calculator is designed for planning weight loss.

Next Steps

Now that you know your maintenance calories, explore related Sixpacks.fit tools to take the next step.