Grays to Rads Converter (Gy to rad)
Grays to Rads Converter (Gy to rad)
Convert Grays (Gy) to Rads (rad) instantly. Translate official SI radiation absorbed dose into traditional rad units for health physics, radiation oncology, and dosimetry calculations.
How to Use This Converter
- Enter the value in Grays (Gy) you want to convert.
- Ensure the “From” selector is set to Grays (Gy).
- Ensure the “To” selector is set to Rads (rad).
- The converted absorbed dose in Rads (rad) calculates instantly in the result box.
Grays (Gy) to Rads (rad) Formula
To convert from Grays (Gy) to Rads (rad), use the exact physical definition relationship:
Primary Formula:
rad = Gy × 100
Calculation Examples
- Example 1: 1 Gy = 100 rad
- Example 2: 2 Gy = 200 rad (standard single radiation therapy daily fraction)
- Example 3: 4.5 Gy = 450 rad (human LD50/60 radiation threshold)
- Example 4: 50 Gy = 5,000 rad (cumulative tumor treatment target dose)
Grays (Gy) to Rads (rad) Conversion Table
| Grays (Gy) | Rads (rad) |
|---|---|
| 0.01 Gy | 1 rad |
| 0.05 Gy | 5 rad |
| 0.1 Gy | 10 rad |
| 0.5 Gy | 50 rad |
| 1 Gy | 100 rad |
| 2 Gy | 200 rad |
| 5 Gy | 500 rad |
| 10 Gy | 1,000 rad |
Frequently Asked Questions
How many Rads are in 1 Gray?
Exactly 100 Rads. One Gray equals 100 Rads (1 Gy = 100 rad). Conversely, 1 Rad equals 0.01 Grays (1 rad = 0.01 Gy = 10 mGy).
What is the difference between Absorbed Dose (Gy) and Equivalent Dose (Sv)?
Absorbed dose (measured in Grays or rads) quantifies the pure physical energy deposited in matter (1 Gy = 1 J/kg). Equivalent dose (measured in Sieverts or rem) multiplies absorbed dose by a radiation weighting factor (W_R) to reflect the biological severity of specific radiation types (e.g., alpha particles have W_R = 20, whereas photons have W_R = 1).
Why did the Gray replace the Rad in scientific standards?
The International Commission on Radiation Units and Measurements (ICRU) and the General Conference on Weights and Measures (CGPM) adopted the Gray in 1975 to integrate radiation dosimetry directly into the coherent SI metric framework (joules per kilogram), eliminating cumbersome CGS conversion factors.