What is the difference between BMR and RMR?

BMR requires strict testing conditions like a 12-hour fast and waking rest. RMR measures resting metabolism under general conditions and includes minor digestive energy, making it 5-10% higher than BMR.

How do I calculate total calories using BMR?

Multiply your BMR by an activity factor (e.g., 1.2 for sedentary, 1.55 for moderate exercise) to get your Total Daily Energy Expenditure (TDEE).

Can I increase my BMR?

Yes, the best way to raise your BMR is by building lean muscle through resistance training, as muscle tissue is more metabolically active than fat.

What happens if I eat fewer calories than my BMR?

Eating below BMR for long periods can trigger metabolic slowdown, fatigue, muscle loss, and nutritional deficiencies, as the body lacks baseline energy for vital organs.

Is BMR Calculator — Basal Metabolic Rate Tool free to use?

Yes, this tool is free to use on Toolfix.info.

Do I need to create an account?

No account is required for basic use of this online tool.

Can I use this tool on mobile?

Yes, the tool is designed to work on desktop, tablet, and mobile browsers.

BMR (Basal Metabolic Rate) is the number of calories your body needs to perform basic life-sustaining functions like breathing, circulation, and cell production at rest.

What formula does this calculator use?

This calculator uses both the Mifflin-St Jeor and Harris-Benedict equations, which are the most widely accepted formulas for estimating BMR.

Does BMR change with age?

Yes, BMR typically decreases by about 1-2% per decade after age 20 due to loss of muscle mass and metabolic slowdown.

BMR Calculator — Basal Metabolic Rate Tool

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