The article discusses the relationship between the age of laboratory rats and humans, emphasizing the need to consider differences in their anatomy, physiology, and development when interpreting research findings. Laboratory rats are widely used in biomedical research due to their role as a model mammalian system. However, accurately correlating their age with that of humans remains a challenge. The review highlights various methods used to estimate rat age, including eye lens weight, molar tooth development, endosteal layers in the tibia, and musculoskeletal growth. These methods are relative and not always precise. Rats grow rapidly and reach sexual maturity at around 6 weeks, while humans reach puberty at about 11-12 years. Social maturity in rats occurs around 5-6 months. The article also discusses the different phases of rat life, including weaning, puberty, and adulthood, and how these compare to human development. It notes that one human year is roughly equivalent to 42.4 rat days during the weaning phase, 3.3 rat days during puberty, and 10.5 rat days during adolescence. In the aged phase, one human year is approximately 17.1 rat days. The review concludes that while rats are essential in biomedical research, they are not miniature humans. Differences in their anatomy, physiology, and development must be considered when analyzing research results, especially when age is a critical factor. Understanding these differences is crucial for accurate interpretation of experimental data and for selecting appropriate dosages in research involving rats.The article discusses the relationship between the age of laboratory rats and humans, emphasizing the need to consider differences in their anatomy, physiology, and development when interpreting research findings. Laboratory rats are widely used in biomedical research due to their role as a model mammalian system. However, accurately correlating their age with that of humans remains a challenge. The review highlights various methods used to estimate rat age, including eye lens weight, molar tooth development, endosteal layers in the tibia, and musculoskeletal growth. These methods are relative and not always precise. Rats grow rapidly and reach sexual maturity at around 6 weeks, while humans reach puberty at about 11-12 years. Social maturity in rats occurs around 5-6 months. The article also discusses the different phases of rat life, including weaning, puberty, and adulthood, and how these compare to human development. It notes that one human year is roughly equivalent to 42.4 rat days during the weaning phase, 3.3 rat days during puberty, and 10.5 rat days during adolescence. In the aged phase, one human year is approximately 17.1 rat days. The review concludes that while rats are essential in biomedical research, they are not miniature humans. Differences in their anatomy, physiology, and development must be considered when analyzing research results, especially when age is a critical factor. Understanding these differences is crucial for accurate interpretation of experimental data and for selecting appropriate dosages in research involving rats.