Calorie Calculator Guide
Reference for estimating BMR, TDEE, and maintenance calories with Mifflin-St Jeor, activity multipliers, and clear limitations.
Quick answer
Use the Calorie Calculator to estimate basal metabolic rate and daily maintenance calories. The result is a planning baseline, not medical, nutrition, or weight-loss advice.
What this tool does
- Estimates BMR with the Mifflin-St Jeor equation
- Applies an activity multiplier to estimate TDEE
- Supports US and metric input
- Shows maintenance, mild deficit, and mild surplus planning numbers
Supported input
- Age
- Height
- Weight
- Sex value used by the equation
- Activity level
Data handling and processing behavior
Calculations are handled in the browser for this tool based on the current public implementation. Avoid entering sensitive health details unless you have reviewed the implementation and your own data handling requirements.
Step-by-step use
- Choose US or metric units.
- Enter age, height, weight, and the sex value used by the equation.
- Pick the activity level that best matches typical daily movement and training.
- Review BMR and maintenance calories.
- Treat the result as a starting estimate and adjust with professional guidance or real-world observation.
Common errors
Choosing an activity level too high. Broad multipliers can overestimate daily calorie needs.
Treating the estimate as exact. Metabolism, activity, medications, tracking accuracy, and health status vary.
Using aggressive changes without context. Large calorie changes should be discussed with qualified professionals.
Limits
This tool uses predictive equations. It does not measure metabolism, account for medical conditions, or replace professional advice.
Next steps
- Calorie Calculator — open the tool
- BMI Calculator — review height and weight context
- Sleep Cycle Calculator — plan sleep timing
- Percentage Calculator — calculate changes and ratios