Gray is absorbed dose in joules per kilogram.
Gray to Attogray
Convert Gray (Gy) to Attogray (aGy) instantly. Free online radiation converter with formulas, tables and examples.
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Convert radioactivity, absorbed dose, and equivalent dose units by compatible radiation family.
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Some unit families need one extra value for a physically accurate result.
Attogray is 1e-18 gray units.
aGy = Gy × 1e+18
Results update instantly for Gray to Attogray conversions.
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Formula
1 Gray = 1e+18 Attogray
aGy = Gy × 1e+18
Gy = aGy ÷ 1e+18
Conversion table
| 1 Gy | 1e+18 aGy |
| 2 Gy | 2e+18 aGy |
| 5 Gy | 5e+18 aGy |
| 10 Gy | 1e+19 aGy |
| 20 Gy | 2e+19 aGy |
| 50 Gy | 5e+19 aGy |
| 100 Gy | 1e+20 aGy |
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Frequently asked questions
How many Attograys are in one Gray?
One Gray equals 1e+18 Attograys.
How do I convert Gray to Attogray?
Multiply the number of Grays by 1e+18 to get Attograys. To go the other way, multiply Attograys by 1e-18 (or divide by 1e+18) to get Grays.
Is this conversion exact?
Yes. This conversion uses the exact defined relationship between Gray and Attogray, so the result shown is mathematically precise (rounded only for display).
When is Gray to Attogray conversion commonly used?
It is commonly used in nuclear medicine, radiation safety, health physics, and scientific research involving radioactivity and radiation dose.
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About this conversion
Gray and Attogray are units used in the radiation family of measurements. Both units measure absorbed radiation dose (energy deposited per unit mass). This converter uses the precise relationship 1 Gray = 1e+18 Attograys (equivalently 1 Attogray = 1e-18 Grays), so results stay accurate for nuclear medicine, radiation safety, health physics, and scientific research.