Radiation Dose

Convert gray to rad

1 gray equals 100 rads. Enter a value below to convert instantly.

1 Gy
100 rad

Multiply the number of grays by 100 to get rads. How this is calculated

Need the other direction? Convert rad to gray →

Formula

Multiply the number of grays by 100 to get rads.

Step by step

  1. Start with 1 Gy.
  2. Multiply by the conversion factor 100.
  3. 1 × 100 = 100 rad.

Grays to Rads conversion table

Conversion table from Grays to Rads
Grays (Gy) Rads (rad)
1 100
2 200
5 500
10 1,000
20 2,000
50 5,000
100 10,000

Convert Gray to other radiation dose units

1 Gy expressed in every other radiation dose unit on this site.

  • Kilogray kGy 0.001
  • Milligray mGy 1,000
  • Microgray µGy 1,000,000
  • Rad rad 100
  • Millirad mrad 100,000
  • Joule per Kilogram J/kg 1
  • Joule per Centigram J/cg 0.00001
  • Joule per Milligram J/mg 0.000001
  • Megagray MGy 0.000001
  • Dekagray daGy 0.1
  • Decigray dGy 10
  • Exagray EGy 1e-18
  • Petagray PGy 1e-15
  • Teragray TGy 1e-12
  • Gigagray GGy 1e-9
  • Hectogray hGy 0.01
  • Nanogray nGy 1,000,000,000
  • Picogray pGy 1,000,000,000,000
  • Femtogray fGy 1,000,000,000,000,000
  • Attogray aGy 1e+18
  • Joule per Gram J/g 0.001
  • Erg per Gram erg/g 10,000
  • Sievert Sv 1
  • Millisievert mSv 1,000
  • Microsievert µSv 1,000,000
  • Nanosievert nSv 1,000,000,000
  • Rem rem 100
  • Millirem mrem 100,000

About the gray

The gray (Gy) is a SI unit of radiation dose. SI absorbed dose: one joule of radiation energy per kilogram of matter.

About the rad

The rad (rad) is a Other unit of radiation dose.

Where this conversion is used

Converting grays to rads comes up when medical imaging, occupational safety, and radiotherapy planning. Grays measure absorbed energy while sieverts weight it for biological harm; they match one-for-one only for X-rays, gamma, and beta radiation.

Related conversions

Frequently asked questions

How many rads are in a gray?

One gray equals 100 rads.

How do you convert grays to rads?

Multiply the number of grays by 100 to get rads.

What is 1 rad in grays?

One rad equals 0.01 grays.

When would I convert grays to rads?

This conversion is common when medical imaging, occupational safety, and radiotherapy planning.

Conversion factors are based on internationally agreed unit definitions. See our methodology and sources for details on how these values are verified.