How this calorie calculator works
The calculator estimates BMR with the Mifflin-St Jeor equation, then multiplies that result by the selected activity factor to estimate daily maintenance calories.
BMR, activity factor and maintenance calories
BMR estimates resting energy use. Activity factors are broad assumptions for usual activity, so real maintenance can vary. Optional adjustments are user-entered and are not recommendations.
What this tool does not include
This calculator does not prescribe calorie intake, diets, weight loss, treatment or medical nutrition therapy. It is not designed for children or teens, pregnancy, eating disorder contexts or medical conditions.
Key terms and assumptionsFormula notes, key terms, source assumptions and limits used in this calculator.
- BMR foundation
- The calculator uses the same Mifflin-St Jeor BMR estimate as the BMR Calculator.
- Activity factor
- Maintenance calories are estimated by multiplying BMR by the selected broad activity factor.
- Custom adjustment
- Optional adjustments are user-entered and are not recommendations, diet plans or treatment guidance.
- Formula limits
- Daily calorie estimates vary with body composition, health status, activity measurement and formula limits.
Related calculators
Browse the Health & Fitness calculators hub for related calculators.
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FAQs
What are maintenance calories?
They are an estimate of calories that would roughly match daily energy use based on the entered assumptions.
Is this the same as BMR?
No. BMR estimates resting energy use. Maintenance calories multiply BMR by an activity factor.
Which activity level should I choose?
Choose the closest general match. Activity factors are broad estimates and can be inaccurate.
Does this calculator tell me how many calories I should eat?
No. It provides a formula-based estimate, not a recommendation.
Can I add a calorie adjustment?
Yes. The custom adjustment is entered by you and is not recommended by the tool.
Is this calculator suitable for pregnancy?
No. This calculator is not designed for pregnancy.
Can teenagers use this calculator?
No. This calculator is scoped to adults.
Why can estimates vary so much?
Formula limits, body composition, activity tracking, health factors and measurement assumptions all affect real-world energy needs.