How to Calculate Metabolic Age

What is Metabolic Age?

Metabolic age compares your BMR to the average for your chronological age. A lower metabolic age (higher BMR than peers) reflects better muscle mass and metabolic health.

Formula

BMR = 88.4 + 13.4*weight + 4.8*height - 5.68*age (Mifflin-St Jeor, male)

BMR: 88 — 88
St: St value — Variable used in the calculation

Step-by-Step Guide

1BMR = 88.4 + 13.4*weight + 4.8*height - 5.68*age (Mifflin-St Jeor, male)
2Metabolic age = Chronological age x (Average BMR for age / Your BMR)
3Higher muscle mass leads to higher BMR and younger metabolic age

Worked Examples

Input

Age 35, BMR 1,900 kcal - average is 1,800 for 35-year-olds

Result

Metabolic age approx 33 - two years younger metabolically

Frequently Asked Questions

What is Metabolic Age Calc?

Metabolic age compares your BMR to the average for your chronological age. A lower metabolic age (higher BMR than peers) reflects better muscle mass and metabolic health

How accurate is the Metabolic Age Calc calculator?

The calculator uses the standard published formula for metabolic age calc. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Metabolic Age Calc calculator use?

This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Metabolic Age Calc calculator use?

The core formula is: BMR = 88.4 + 13.4*weight + 4.8*height - 5.68*age (Mifflin-St Jeor, male). Each step in the calculation is shown so you can verify the result manually.

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