The normal range of creatinine levels can vary depending on factors such as age, sex, muscle mass, and individual health conditions. In general, for adult males, the normal range is approximately 0.6 to 1.2 milligrams per deciliter (mg/dL), while for adult females, it is around 0.5 to 1.1 mg/dL. However, it is important to note that these ranges can vary between laboratories, and specific reference ranges may be adjusted based on factors such as age. It is recommended to consult with a healthcare professional who can interpret your specific creatinine levels in the context of your medical history, age, sex, and other relevant factors to provide an accurate assessment of kidney function.