About This Tool
Total Daily Energy Expenditure (TDEE) represents the total number of calories your body burns in a 24-hour period, combining your basal metabolic rate with the energy used for physical activity and food digestion. Unlike BMR, which only measures resting energy needs, TDEE gives you the complete picture of your daily calorie burn. This is the number you need to know for any weight management goal: eat below it to lose weight, match it to maintain, or exceed it to gain. This TDEE calculator uses the Mifflin-St Jeor equation to compute your BMR, then multiplies it by a research-based activity factor. What makes this tool especially useful is that it shows your estimated TDEE across all five activity levels simultaneously, so you can see how changes in your exercise habits would affect your daily calorie needs. It also provides ready-made calorie targets for common goals: aggressive cut (minus 500 calories), moderate cut (minus 250), maintenance, lean bulk (plus 250), and full bulk (plus 500). Understanding the relationship between BMR, activity, and total expenditure is essential for anyone serious about body composition. Your BMR typically accounts for 60 to 75 percent of your TDEE, physical activity contributes 15 to 30 percent, and the thermic effect of food (energy used for digestion) accounts for roughly 10 percent. The activity multiplier captures the physical activity portion and adjusts your baseline accordingly. By selecting the correct activity level and using the calorie targets provided, you can set precise nutritional goals without guesswork.
TDEE vs. BMR: The Key Difference
BMR (Basal Metabolic Rate) is the number of calories your body needs to perform basic life-sustaining functions while completely at rest: breathing, pumping blood, maintaining body temperature, and repairing cells. If you spent an entire day lying still in bed without eating, your BMR is approximately how many calories you would burn.
TDEE adds everything else on top of BMR:
- Exercise Activity Thermogenesis (EAT): Planned exercise sessions like running, weight training, or cycling.
- Non-Exercise Activity Thermogenesis (NEAT): Unstructured movement such as walking, fidgeting, cooking, and cleaning. NEAT can vary by 500+ calories between individuals.
- Thermic Effect of Food (TEF): Energy required to digest, absorb, and metabolize food. Protein has the highest TEF at 20 to 30 percent, followed by carbohydrates (5 to 10%) and fat (0 to 3%).
For practical purposes, the activity multiplier in this calculator captures the combined effect of EAT, NEAT, and TEF based on your general lifestyle and exercise habits.
How to Choose Your Activity Level
The most common mistake when calculating TDEE is overestimating activity level. Here are detailed guidelines for each tier:
- Sedentary (x1.2): You work a desk job and do not exercise regularly. Your daily step count is under 5,000. Most of your leisure time involves sitting.
- Lightly Active (x1.375): You exercise 1 to 3 days per week or have an active commute (walking, cycling). Your daily step count is 5,000 to 7,500.
- Moderately Active (x1.55): You exercise 3 to 5 days per week for 30 to 60 minutes per session. This is the correct level for most recreational gym-goers.
- Active (x1.725): You exercise intensely 6 to 7 days per week, or you have a physically demanding job such as construction, nursing, or warehouse work.
- Very Active (x1.9): You train intensely every day (often twice) and have a physically active occupation. Common among competitive athletes and military trainees.
When uncertain, start one level lower than you think. Track your weight for 2 to 3 weeks. If you are losing weight unintentionally, move up one level. If gaining, your selected level may be too high.
Using TDEE for Weight Goals
Once you know your TDEE, creating a calorie target for your specific goal is straightforward:
- Fat loss: A deficit of 250 to 500 calories below TDEE per day produces 0.5 to 1 pound of fat loss per week. Larger deficits accelerate results but increase the risk of muscle loss, hormonal disruption, and adherence problems.
- Maintenance: Eating at your TDEE maintains your current weight. This is useful during periods of recovery, performance focus, or body recomposition (simultaneous fat loss and muscle gain at a slow pace).
- Muscle gain: A surplus of 250 to 500 calories above TDEE, combined with progressive resistance training, supports muscle growth while minimizing excess fat gain. Surpluses larger than 500 calories rarely produce additional muscle benefit and mostly increase fat accumulation.
This calculator enforces a minimum calorie floor of 1,200 per day for deficit targets. Sustained intake below this level makes it very difficult to meet essential vitamin and mineral requirements and should only be attempted with medical supervision.
Why TDEE Changes Over Time
Your TDEE is not a fixed number. Several factors cause it to shift over weeks and months:
- Weight changes: As you lose weight, your body requires fewer calories to sustain itself. A person who loses 20 pounds may see their TDEE drop by 100 to 200 calories. Recalculate every 10 to 15 pounds of change.
- Metabolic adaptation: During prolonged calorie deficits, the body becomes more efficient, reducing NEAT and slightly lowering BMR. Periodic "diet breaks" (eating at maintenance for 1 to 2 weeks) can help mitigate this effect.
- Muscle gain: Adding lean mass increases BMR because muscle tissue is more metabolically active than fat tissue. Each pound of muscle burns roughly 6 to 7 calories per day at rest, compared to 2 calories per pound of fat.
- Aging: BMR decreases approximately 1 to 2 percent per decade after age 20, primarily due to declining muscle mass and hormonal changes.
- Seasonal and lifestyle shifts: Activity patterns often change with the seasons, job changes, or life events. Recalculate when your routine shifts significantly.
Treat your TDEE as a working estimate that you refine based on real-world results rather than an exact prescription.
Frequently Asked Questions
What is the most accurate way to determine my TDEE?
Equations like Mifflin-St Jeor provide a solid estimate, but the most accurate approach is empirical tracking. Eat a consistent number of calories for 2 to 3 weeks while weighing yourself daily. If your weight stays stable, that intake is your true TDEE. If you gain or lose, adjust accordingly. This method accounts for individual metabolic variation that no formula can capture, including genetics, gut microbiome differences, and hormonal factors.
Should I eat the same calories every day?
You can choose either a daily fixed target or a weekly calorie budget. Some people prefer "calorie cycling," eating more on training days and less on rest days while keeping the weekly total the same. For example, if your target is 2,500 calories per day (17,500 per week), you might eat 2,800 on training days and 2,200 on rest days. Both approaches produce similar results for weight management; choose whichever is easier to sustain.
How is TDEE different from the calories shown on fitness trackers?
Fitness trackers estimate total calorie burn using heart rate data, motion sensors, and user-entered metrics. Research shows that wrist-based trackers overestimate calorie expenditure by 20 to 40 percent on average. TDEE calculated from a validated equation like Mifflin-St Jeor tends to be more reliable as a baseline. Use tracker data for relative comparisons between days (more active vs. less active) rather than as absolute calorie targets.
Can I increase my TDEE without exercising more?
Yes. Non-exercise activity thermogenesis (NEAT) is a significant contributor to TDEE and can be increased through daily habits:
- Take walking meetings or phone calls
- Use a standing desk for part of the day
- Take stairs instead of elevators
- Park farther from entrances
- Do household chores and gardening
Research shows that NEAT can vary by up to 2,000 calories per day between individuals. Small increases in daily movement accumulate into meaningful calorie burn over time.
Why does the calculator show a 1,200 calorie minimum?
Most nutrition guidelines recommend that adults consume no fewer than 1,200 calories per day (some guidelines set the floor at 1,500 for men). Below this threshold, it becomes very difficult to obtain adequate vitamins, minerals, protein, and essential fatty acids from food alone. Very low calorie diets (800 to 1,000 calories) do exist as medically supervised interventions for severe obesity, but they require professional monitoring, supplementation, and are not intended for general use.
How do I account for a job that mixes sitting and standing?
Many jobs involve a mix of desk work and walking or standing (teaching, nursing, retail). For these roles, "Lightly Active" (x1.375) is usually appropriate if you do not also exercise regularly outside of work. If you add 3 to 5 workouts per week on top of an active job, "Moderately Active" to "Active" is a better fit. The key is to consider your total daily movement pattern, not just your structured exercise sessions.