Metabolic age calculator

Metabolic age is an estimated biological age expressed in years, determined by comparing your BMR to average BMR values for people of the same gender in successive age groups. A lower metabolic age than your real age means your metabolism works faster than that of your peers.

The calculator first computes your individual BMR using the Mifflin–St Jeor method (accounting for weight, height, age and gender), then compares that value to reference BMR values for each age group. Metabolic age corresponds to the group whose average BMR is closest to yours.

BMR (Basal Metabolic Rate) is the minimum number of calories your body burns at rest to maintain basic functions: heartbeat, breathing and body temperature. The higher the BMR, the faster the metabolism and the lower the metabolic age.

A metabolic age higher than your actual age may suggest a slower metabolism, often linked to excess body fat, a sedentary lifestyle or poor diet. It is not a medical diagnosis — consult a doctor or dietitian and focus on physical activity and a balanced diet.

You can lower metabolic age through regular strength and aerobic exercise (which increases muscle mass and raises BMR), maintaining a healthy body weight, getting 7–9 hours of sleep, avoiding prolonged sitting, and eating a protein-rich balanced diet.

Yes — men typically have a higher BMR than women of the same age at similar weight and height, mainly due to greater muscle mass. The calculator accounts for gender both when computing BMR and when comparing against reference values for the appropriate group.

BMR naturally declines with age — estimates suggest metabolism slows by about 1–2% per decade after age 30. This is mainly due to progressive muscle loss (sarcopenia). Older adults therefore need fewer calories to maintain weight, making physical activity key to preserving metabolic fitness.

Not exactly. Biological age is a broader concept encompassing many health indicators: cardiovascular status, bone density, telomere length and inflammatory markers. Metabolic age refers specifically to the efficiency of your basal metabolism and is one component of biological age.

The calculator uses the Mifflin–St Jeor equation, considered the most accurate formula for estimating BMR in healthy adults — typical error is about ±10%. Alternatives include Harris–Benedict (older, slightly less precise) and Katch–McArdle (requires lean body mass).

No — metabolic age depends on BMR, which is influenced by weight, height, age and gender. Body composition plays a key role: two people of the same weight can have different BMRs if their muscle-to-fat ratio differs. Muscle burns more energy at rest than fat, so a muscular person will have a higher BMR and lower metabolic age.