Adaptive TDEE calculator
Use a log of daily intake and repeated weigh-ins to estimate maintenance calories from your own trend, rather than relying only on a population equation.
Searching for an AI adaptive tdee calculator? This one uses a standard published formula, not an AI model, so you can see exactly how your number is made. See how BiteCal AI tracks meals against it.
Your tracking data
Enter at least five weigh-ins spanning at least 14 days. Use kilograms and ISO dates.
Adaptive maintenance estimate
Add a valid intake estimate and five or more dated weigh-ins spanning at least 14 days.
Add at least 5 valid weigh-ins across 14 or more days and a positive average daily calorie intake.
Your result explained
The adaptive estimate combines your average logged energy intake with the slope of your body-weight trend. A falling trend implies estimated expenditure above recorded intake; a rising trend implies it below.
How it’s calculated
A least-squares line estimates weight change in kilograms per day. Estimated TDEE = average logged intake − (weight slope × 7,700 kcal/kg). The 7,700 rule is a simplified energy-balance approximation, not a dynamic physiology model.
Worked example: If average intake is 2,200 kcal/day and the trend falls by 0.02 kg/day, the estimate is 2,200 − (−0.02 × 7,700) = 2,354 kcal/day.
Limits and accuracy
This method depends on accurate food records and enough consistent measurements. Water shifts, changes in logging, and short observation windows can dominate the signal. R² and confidence labels describe the fit to these entries, not clinical certainty or future weight change.
Frequently asked questions
How many weigh-ins do I need?
This calculator requires at least five valid weigh-ins spread across at least 14 days. More consistent entries over a longer period can provide a clearer trend.
How does adaptive TDEE differ from a standard TDEE calculator?
A standard TDEE calculator uses a body-size equation and activity factor. This estimator uses logged intake and a measured weight trend to infer expenditure during the logged period.
What does a low confidence result mean?
It means the data show limited or noisy trend information. It does not mean that the estimate is clinically validated; continue consistent logging rather than reacting to a short-term number.
Why can my estimate change over time?
Body weight, activity, intake, and logging quality change. Re-estimating across a new consistent period can produce a different result.
Is this result medical advice?
No. It is a mathematical estimate from user-entered records and should not replace individualized advice from a qualified health professional.
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Estimates only. This is not medical advice. Last reviewed: 20 October 2026.