Radiation Dose Converter
Convert radiation dose between SI and traditional units used in radiology, nuclear medicine, and health physics. The sievert (Sv) is the SI unit for effective dose (biological impact). The gray (Gy) measures absorbed dose. The rem and rad are older traditional units still used in the United States.
Frequently Asked Questions
Gray (Gy) measures absorbed dose — energy deposited per kilogram of tissue. Sievert (Sv) measures effective dose — the biological effect, which accounts for radiation type (alpha, beta, gamma). For gamma rays, 1 Gy ≈ 1 Sv.