Your thyroid hormone may vary depending on your age, sex, and condition (like pregnancy, chronic condition or complication). For example, a 30-year-old woman may have normal TSH around 4.2 mU/L, while a 90-year-old man may reach 8.9 mU/L at their upper limits. Besides this, your level of stress, diet, and medications, and menses period can fluctuate your level of thyroid hormone. An average general range for reference is as below: -Normal TSH range should be 0.4 - 4.0 mIU/L -Normal T3 range should be 0.2 - 0.5 ng/dl -Normal T4 range should be 0.8 - 1.8 ng/dl