About this calculator
This TDEE calculator estimates total daily energy expenditure by combining the Mifflin-St Jeor resting energy equation with an activity factor. It is useful for estimating maintenance calories before planning a deficit or surplus.
The result is only a starting estimate. Real maintenance intake can differ because wearable calorie estimates, food tracking, adaptive metabolism, and daily activity vary.
Calculates Mifflin-St Jeor resting energy needs, then multiplies by a selected activity factor. This is a planning estimate, not an individualized metabolic test.
Activated — calorie maintenance estimate
Educational estimate only; not a diagnosis, prescription, or treatment plan.
Formula and method
TDEE = Mifflin-St Jeor resting energy estimate × activity factor. Activity factors are broad categories, so the result should be adjusted using weight trend, symptoms, and clinician or dietitian guidance when relevant.
Limitations and when not to rely on this result
- Educational estimate only; not a diagnosis, prescription, or treatment plan.
- Result depends on accurate inputs and may not apply to complex medical situations.
- Use clinician judgment, local guidance, and urgent care pathways when symptoms are severe.
Frequently asked questions
What does TDEE mean? +
TDEE stands for total daily energy expenditure: the approximate calories your body uses in a day including resting needs and activity.
Why is my TDEE only an estimate? +
Activity factors are broad and cannot capture every difference in movement, training, food absorption, body composition, illness, and metabolic adaptation.
Can I use this for weight loss? +
It can provide a starting point, but aggressive deficits can be unsafe. People who are pregnant, underweight, medically complex, or have eating-disorder history should seek professional guidance.
What activity factor should I choose? +
Choose the closest average week, including job movement and exercise. If unsure, choose a lower factor and adjust based on weight trend.
Is TDEE the same every day? +
No. It changes with exercise, steps, sleep, illness, training load, and body weight changes.