About
This site exists to answer one question well: how much should I eat? Every tool here is free, runs entirely in your browser, and gives you the same formulas used by dietitians – without accounts, downloads or paywalls.
Who runs this site
TDEE Calculator (tdeetool.com) is an independent, free calculator site. It is not run by a medical practice, and its content has not been written or reviewed by doctors or dietitians. Questions or corrections are welcome through the contact page.
How the numbers are produced
Every result is an estimate calculated in your browser from standard, published equations and the details you enter (age, sex, height, weight and activity level). Nothing is measured, so your real needs can differ. The tools are for adults (18+) only and reject younger ages.
The formulas
- BMR and TDEE: the Mifflin-St Jeor equation, rated the most accurate predictive formula for healthy adults by the Academy of Nutrition and Dietetics, multiplied by standard activity factors (1.2-1.9).
- BMI: weight divided by height squared, with the CDC adult categories.
- Deficit planning: the 3,500 kcal-per-pound approximation, which research by Kevin Hall shows tends to overestimate real-world loss, so treat timelines as rough estimates. Targets are never set below 1,200 kcal (women) or 1,500 kcal (men); these minimums are a common rule of thumb, not a guarantee that a plan is safe for you. If your estimated maintenance is at or below the minimum, the tools give no weight-loss target, and every timeline is an estimate based on the actual deficit after that minimum is applied.
- Macros: protein at 1 g per pound of body weight, fat at 25% of calories, carbohydrates filling the remainder, using the 4 / 9 / 4 kcal-per-gram values published by the Institute of Medicine. Protein guidance draws on a 2018 meta-analysis.
Why the tools are free
Every calculator is free to use, with no sign-up, email address or subscription. To keep it that way, the site may show ads in the future; if it does, the privacy policy explains how they work.
Your privacy
Calculations run on your device – your age, weight and height are never sent to a server. See the privacy policy for details on cookies and data.
A note on accuracy
These tools produce estimates for healthy adults and are not medical advice. Pregnant or breastfeeding women, people under 18, and anyone with a medical condition affecting weight or metabolism should work with a physician or registered dietitian.