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Metabolic Age Calculator

Your metabolic age compares your Basal Metabolic Rate (BMR) to the average BMR for different age groups. If your BMR is higher than average for your age, your metabolic age is younger - meaning your body burns energy more efficiently. A lower BMR suggests an older metabolic age.

1

Enter your details

Gender
years
kg
cm

Your Metabolic Age

Example

Example figures, not your own. Worked for a 35 year old man of 80 kg and 175 cm. Enter your own details and press Calculate.

Metabolic Age

25years

Actual Age

35years

Your BMR

1,724kcal/day

7,212 kJ/day

10 years younger than your age

Excellent! Your metabolism is performing significantly better than average for your age. This suggests good muscle mass and overall fitness.

How It Works

First, your BMR is calculated using the Mifflin-St Jeor equation. Then it is compared against average BMR values for each age group (based on average height and weight data). Your metabolic age is the age group whose average BMR most closely matches yours. Regular exercise and more muscle mass lead to a younger metabolic age.

How to use it

  1. 1Select your gender
  2. 2Enter your chronological age
  3. 3Enter your weight in kilograms
  4. 4Enter your height in centimetres
  5. 5Click "Calculate" to see your metabolic age compared to your actual age

Quick Reference

Age GroupAvg Male BMR (kcal)Avg Female BMR (kcal)
18-201,750-1,7601,400-1,410
25-301,700-1,7251,360-1,380
35-401,650-1,6751,320-1,340
45-501,590-1,6201,270-1,295
55-601,520-1,5551,210-1,240
65-701,440-1,4801,150-1,180
75-801,360-1,4001,090-1,120

Average BMR values based on typical height and weight for each age group. Individual BMR varies with muscle mass and body composition.

Mifflin-St Jeor BMR Equation

Men: BMR = 10 x W + 6.25 x H - 5 x A + 5 Women: BMR = 10 x W + 6.25 x H - 5 x A - 161
W
= weight in kilograms
H
= height in centimetres
A
= age in years

Your BMR is compared to average BMR values for each age group. Metabolic age is the age group whose average BMR best matches yours.

Frequently Asked Questions

What is metabolic age?
Metabolic age is a comparison of your Basal Metabolic Rate to the average BMR of people at various ages. If your BMR matches that of an average 25-year-old, your metabolic age is 25, regardless of your actual age. It reflects your metabolic health.
How can I improve my metabolic age?
Build and maintain muscle mass through resistance training, as muscle burns more energy at rest than fat. Stay physically active, eat adequate protein, sleep well, and maintain a healthy weight. These factors all increase BMR and lower metabolic age.
Is metabolic age the same as biological age?
Not exactly. Metabolic age focuses specifically on your metabolism (BMR), while biological age considers a broader range of health factors including cardiovascular fitness, immune function, and cellular health. They are related but measure different aspects.
Why does metabolic age increase with weight loss?
When you lose weight, your BMR decreases because your body has less mass to maintain. This can temporarily increase your metabolic age. Preserving muscle through strength training and adequate protein intake helps maintain a healthy metabolic age during weight loss.

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