Gray is absorbed dose in joules per kilogram.
Gray to Femtogray
Convert Gray (Gy) to Femtogray (fGy) 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.
Femtogray is 1e-15 gray units.
fGy = Gy × 1e+15
Results update instantly for Gray to Femtogray conversions.
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Formula
1 Gray = 1e+15 Femtogray
fGy = Gy × 1e+15
Gy = fGy ÷ 1e+15
Conversion table
| 1 Gy | 1e+15 fGy |
| 2 Gy | 2e+15 fGy |
| 5 Gy | 5e+15 fGy |
| 10 Gy | 1e+16 fGy |
| 20 Gy | 2e+16 fGy |
| 50 Gy | 5e+16 fGy |
| 100 Gy | 1e+17 fGy |
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Frequently asked questions
How many Femtograys are in one Gray?
One Gray equals 1e+15 Femtograys.
How do I convert Gray to Femtogray?
Multiply the number of Grays by 1e+15 to get Femtograys. To go the other way, multiply Femtograys by 1e-15 (or divide by 1e+15) to get Grays.
Is this conversion exact?
Yes. This conversion uses the exact defined relationship between Gray and Femtogray, so the result shown is mathematically precise (rounded only for display).
When is Gray to Femtogray 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 Femtogray 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+15 Femtograys (equivalently 1 Femtogray = 1e-15 Grays), so results stay accurate for nuclear medicine, radiation safety, health physics, and scientific research.