Absorbed Radiation Dose Converter
Convert absorbed radiation dose between gray (Gy), rad, sievert (Sv), and rem. Gray measures absorbed energy; sievert accounts for biological effectiveness.
Common Absorbed Radiation Dose Conversions
| From | To |
|---|---|
| 1 Gy | 100 rad |
| 1 Sv | 100 rem |
| 1 mGy | 0.001 Gy |
| 1 mSv | 0.001 Sv |
| Lethal dose (LD50) | ~4–5 Gy |
| Annual background | ~3 mSv |
| Chest CT scan | ~7 mSv |
Absorbed Radiation Dose Unit Definitions
- Gray (Gy)
- SI unit of absorbed dose = 1 J/kg.
- Sievert (Sv)
- SI unit of effective dose (biologically weighted).
- Rad
- 0.01 Gy. Legacy unit.
- Rem
- 0.01 Sv. Legacy unit.
Frequently Asked Questions
What is the difference between gray and sievert?
Gray (Gy) is absorbed energy per unit mass. Sievert (Sv) = Gy × radiation weighting factor. For X-rays and gamma rays, 1 Gy = 1 Sv. For alpha particles, 1 Gy = 20 Sv.
What is a lethal radiation dose?
A whole-body dose of 4–5 Gy has ~50% chance of death within 30 days (LD50/30) without medical treatment.
How much radiation does a CT scan deliver?
A chest CT delivers ~7 mSv (0.007 Sv). A full-body CT can be 10–30 mSv. For comparison, natural background is ~3 mSv per year.