Gray is absorbed dose in joules per kilogram.
Gray to Zeptogray
Convert Gray (Gy) to Zeptogray (zGy) instantly. Free online radiation converter with formulas, tables and examples.
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Radiation Converter
Convert radioactivity, absorbed dose, and equivalent dose units by compatible radiation family.
Context values
Some unit families need one extra value for a physically accurate result.
Zeptogray is 1e-21 gray units.
zGy = Gy × 1e+21
Results update instantly for Gray to Zeptogray conversions.
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Formula
1 Gray = 1e+21 Zeptogray
zGy = Gy × 1e+21
Gy = zGy ÷ 1e+21
Conversion table
| 1 Gy | 1e+21 zGy |
| 2 Gy | 2e+21 zGy |
| 5 Gy | 5e+21 zGy |
| 10 Gy | 1e+22 zGy |
| 20 Gy | 2e+22 zGy |
| 50 Gy | 5e+22 zGy |
| 100 Gy | 1e+23 zGy |
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Frequently asked questions
How many Zeptograys are in one Gray?
One Gray equals 1e+21 Zeptograys.
How do I convert Gray to Zeptogray?
Multiply the number of Grays by 1e+21 to get Zeptograys. To go the other way, multiply Zeptograys by 1e-21 (or divide by 1e+21) to get Grays.
Is this conversion exact?
Yes. This conversion uses the exact defined relationship between Gray and Zeptogray, so the result shown is mathematically precise (rounded only for display).
When is Gray to Zeptogray 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 Zeptogray 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+21 Zeptograys (equivalently 1 Zeptogray = 1e-21 Grays), so results stay accurate for nuclear medicine, radiation safety, health physics, and scientific research.