BMR Calculator Definition

A BMR (Basal Metabolic Rate) calculator is a tool that estimates the minimum number of calories your body requires to perform fundamental physiological functions at rest—such as breathing, circulation, and cell production. A BMR calculator uses variables like age, gender, weight, and height to provide the foundational baseline needed before calculating total daily energy expenditure.

Related Calculators

Use these tools to compute values based on this definition.

Further Reading

Deep dive into the math and concepts with our comprehensive guides.

Core Glossary Term

Read the formal mathematical definition.

Worked Examples

Step-by-step calculations showing how to apply this concept.

Health

Basal Metabolic Rate of a 30-Year-Old Female

This individual requires 1,373 calories per day just to keep her body alive at rest. She should never eat below this number, as it can cause metabolic damage and muscle loss.

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Frequently Asked Questions

Is BMR the same as resting metabolic rate (RMR)?

They are very similar. BMR is slightly more strict and measures calories burned under absolute rest conditions, while RMR is a slightly more relaxed measurement.

Which equation does a BMR calculator use?

Most modern BMR calculators use the Mifflin-St Jeor equation, which is widely considered the most accurate standard formula.