Rem is 0.01 sievert.
Rem to Gray
Convert Rem (rem) to Gray (Gy) 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.
Gray is absorbed dose in joules per kilogram.
Gy = rem × 0.01
Results update instantly for Rem to Gray conversions.
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Formula
1 Rem = 0.01 Gray
Gy = rem × 0.01
rem = Gy ÷ 0.01
Conversion table
| 1 rem | 0.01 Gy |
| 2 rem | 0.02 Gy |
| 5 rem | 0.05 Gy |
| 10 rem | 0.1 Gy |
| 20 rem | 0.2 Gy |
| 50 rem | 0.5 Gy |
| 100 rem | 1 Gy |
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Frequently asked questions
How many Grays are in one Rem?
One Rem equals 0.01 Grays.
How do I convert Rem to Gray?
Multiply the number of Rems by 0.01 to get Grays. To go the other way, multiply Grays by 100 (or divide by 0.01) to get Rems.
Is this conversion exact?
Yes. This conversion uses the exact defined relationship between Rem and Gray, so the result shown is mathematically precise (rounded only for display).
When is Rem to Gray 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
Rem and Gray are units used in the radiation family of measurements. Rem measures equivalent radiation dose (biological risk-weighted dose), while Gray measures absorbed radiation dose (energy deposited per unit mass). This page provides the direct numeric ratio between the two units. This converter uses the precise relationship 1 Rem = 0.01 Grays (equivalently 1 Gray = 100 Rems), so results stay accurate for nuclear medicine, radiation safety, health physics, and scientific research.