Adaptive TDEE means your app doesn’t assume a fixed calorie burn. It learns your real maintenance calories from what you eat and how your weight actually changes.

Normal TDEE Most calculators estimate TDEE from age, height, weight, and activity level. That’s just a guess and can be off by hundreds of calories.

Adaptive TDEE Instead of guessing, it updates your TDEE over time using real data:

If you want adaptive TDEE without building your own spreadsheet or system, use the free MacroCodex Android app. It tracks your calorie intake and body weight over time, then estimates your real maintenance calories and updates your targets as your trend changes.

You log:

• Daily calorie intake
• Daily (or frequent) body weight

Keep adding your calorie intake and weight reading each day and after a few readings, MacroCodex will tell you your actual TDEE and calorie intake targets for whatever rate of gain or loss you set, even if your activity level varies week to week.

The system:

• Looks at how your weight trend changes
• Compares expected change vs actual change
• Adjusts your estimated TDEE upward or downward
• Gets more accurate the longer you log data

Simple idea

If you eat 2,300 kcal/day and your weight stays flat for 2–3 weeks → your TDEE ≈ 2,300

If you eat 2,300 and gain weight → your TDEE is lower than 2,300

If you eat 2,300 and lose weight → your TDEE is higher than 2,300

Then it keeps refining this number as new data comes in.

Why it’s better

• Accounts for metabolic adaptation
• Accounts for logging errors
• Accounts for real activity levels
• Works even if user lies about “activity level”
• Gets personalized instead of generic

How apps usually implement it

1. Smooth weight fluctuations
2. Compute daily calorie balance
3. Convert weight change to energy (≈ 7,700 kcal per kg fat)
4. Adjust TDEE estimate gradually
5. Clamp changes to avoid noise

Once you have adaptive TDEE, you can:

• Predict future weight from current intake
• Suggest calories for weight loss/gain targets
• Show when fat loss stalls