Chronological age refers to the age of a person, determined in months, days, and years from the time the person was born, the term is usually used in psychometrics.
On the other hand, the biological age is how the tissues of the body, organs, and systems grow older. It can also be stated that how far away or close the organs are far from age-associated circumstances. A person's biological age is a far better sign of their health than the age in years.
Thus, chronological age is the true age in years, however, biological age can be different on the basis of one's lifestyle choices, and biological age can be younger than chronological age with sufficient rest on the daily basis, good nutrition, consistent exercise, and effective stress management.