Daily Calorie Needs Calculator (TDEE Estimate)
This free Daily Calorie Needs Calculator (US units) estimates your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) using the Mifflin-St Jeor equation. It helps you understand how many calories you need to maintain, lose, or gain weight.
Enter your details to see estimated daily calories to maintain, gain, or lose weight. These estimates are intended for adults age 19 or older and may be inappropriate during pregnancy, illness, or other circumstances requiring individualized nutrition advice.
Daily Calorie Needs Calculator (US Units)
Calculate your TDEE for weight loss, maintenance, or gain.
How the Daily Calorie Calculator Works
The calculator first estimates your Basal Metabolic Rate (BMR) — a prediction of the number of calories your body uses at rest. It then multiplies BMR by your activity level to calculate Total Daily Energy Expenditure (TDEE).
From your estimated maintenance calories, the calculator shows three daily calorie estimates for different weight goals:
- Maintain weight: Eat around the estimated TDEE as a starting point.
- Gain weight: The example adds 15% to maintenance calories. This is a calorie-surplus illustration, not a promise of a particular rate of weight gain.
- Lose weight: The example subtracts 15% from maintenance calories. This is a calorie-deficit illustration, not a promise of a particular rate of weight loss or a recommendation for everyone.
Factors That Affect Your Daily Calorie Needs
Age and Metabolism
Metabolism naturally slows with age, meaning older adults generally need fewer calories.
Gender
Men typically have higher calorie needs due to greater muscle mass and higher BMR.
Body Size (Weight & Height)
Larger bodies require more energy to maintain basic functions.
Activity Level
More physical activity significantly increases daily calorie requirements.
Frequently Asked Questions
How accurate is this calorie calculator?
It predicts resting energy expenditure with the Mifflin–St Jeor equation, then applies a broad activity factor. Real energy needs vary, sometimes substantially. The tool is not a substitute for clinical nutrition assessment.
What is the difference between BMR and TDEE?
BMR is calories burned at complete rest. TDEE includes all daily activity and is the number most people use for diet planning.
How many calories should I eat to lose weight?
The calculator displays a daily calorie estimate for weight loss that is 15% below estimated maintenance. This is an illustrative starting point, not a guaranteed result or a suitable plan for everyone. A clinician or registered dietitian can help assess individual needs.
Should I eat the same calories every day?
Consistency helps, but some people prefer cycling calories (higher on workout days, lower on rest days).
Can this calculator be used for muscle gain?
It shows estimated daily calories for weight gain using a 15% surplus over estimated maintenance. This does not predict muscle gain or guarantee a specific change in body weight; resistance training and adequate nutrition also matter.
Method and source
Resting energy expenditure is predicted from weight, height, age, and the equation’s female/male coefficient. The activity multiplier is a rough proxy for total daily expenditure, not a direct measurement. The original study used adults, so this tool is limited to age 19 and above.