Gray is absorbed dose in joules per kilogram.
Gray to Millisievert
Convert Gray (Gy) to Millisievert (mSv) 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.
Millisievert is 0.001 sievert units.
mSv = Gy × 1000
Results update instantly for Gray to Millisievert conversions.
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Formula
1 Gray = 1000 Millisievert
mSv = Gy × 1000
Gy = mSv ÷ 1000
Conversion table
| 1 Gy | 1000 mSv |
| 2 Gy | 2000 mSv |
| 5 Gy | 5000 mSv |
| 10 Gy | 10000 mSv |
| 20 Gy | 20000 mSv |
| 50 Gy | 50000 mSv |
| 100 Gy | 100000 mSv |
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Frequently asked questions
How many Millisieverts are in one Gray?
One Gray equals 1000 Millisieverts.
How do I convert Gray to Millisievert?
Multiply the number of Grays by 1000 to get Millisieverts. To go the other way, multiply Millisieverts by 0.001 (or divide by 1000) to get Grays.
Is this conversion exact?
Yes. This conversion uses the exact defined relationship between Gray and Millisievert, so the result shown is mathematically precise (rounded only for display).
When is Gray to Millisievert 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 Millisievert are units used in the radiation family of measurements. Gray measures absorbed radiation dose (energy deposited per unit mass), while Millisievert measures equivalent radiation dose (biological risk-weighted dose). This page provides the direct numeric ratio between the two units. This converter uses the precise relationship 1 Gray = 1000 Millisieverts (equivalently 1 Millisievert = 0.001 Grays), so results stay accurate for nuclear medicine, radiation safety, health physics, and scientific research.