Absorbed Radiation Dose Converter

The absorbed dose (D) is the energy that ionizing radiation leaves in a material, per kilogram of it. Its SI unit is the gray (Gy), one joule per kilogram. The older unit is the rad: 1 Gy = 100 rad.

For X-rays and gamma rays, one gray of dose to the body is one sievert (Sv), the unit of its effect. For a sense of scale, a chest X-ray gives about 0.1 mGy, a CT scan of the abdomen about 10 mGy, and a course of radiotherapy 50–70 Gy, spread over weeks.

The dose rate, per second, is converted in the Radiation Converter.

How to convert absorbed dose units

Type a value into any field, and every other unit is calculated at once. For example, a dose of 193 mGy:

1. In grays: divide by 1,000.

   193 / 1,000 = 0.193 Gy

2. In rads: multiply the grays by 100.

   0.193 × 100 = 19.3 rad

Common conversions

Absorbed dose units

• Gray (Gy): Gray is the SI unit of absorbed dose, where 1 Gray is equal to 1 joule of energy deposited per kilogram of matter, or 1 Gy = 1 J/kg.

• Petagray (PGy): 1 PGy = 10^15 Gy (1,000,000,000,000,000 Gy).

• Teragray (TGy): 1 TGy = 10^12 Gy (1,000,000,000,000 Gy).

• Gigagray (GGy): 1 GGy = 10^9 Gy (1,000,000,000 Gy).

• Megagray (MGy): 1 MGy = 10^6 Gy (1,000,000 Gy).

• Kilogray (kGy): 1 kGy = 10^3 Gy (1,000 Gy).

• Milligray (mGy): 1 mGy = 10^(-3) Gy (0.001 Gy).

• Microgray (μGy): 1 μGy = 10^(-6) Gy (0.000001 Gy).

• Nanogray (nGy): 1 nGy = 10^(-9) Gy (0.000000001 Gy).

• Picogray (pGy): 1 pGy = 10^(-12) Gy (0.000000000001 Gy).

• Femtogray (fGy): 1 fGy = 10^(-15) Gy (0.000000000000001 Gy).

• Rad (rad): The traditional unit for absorbed dose, where 1 rad is equal to 0.01 gray, or 1 rad = 0.01 Gy.

• Millirad (mrad): 1 mrad = 0.001 rad = 0.00001 Gy.

• Joule/kilogram (J/kg): The joule per kilogram is equivalent to Gray, or 1 J/kg = 1 Gy.

• Joule/gram (J/g): 1 J/g = 10^3 J/kg = 1,000 Gy.

• Joule/milligram (J/mg): 1 J/mg = 10^3 J/g = 10^6 J/kg = 1,000,000 Gy.