rad → Gy
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
About this calculator
The rad to Gray (Gy) conversion calculator transforms absorbed radiation dose units. To use it, divide the rad value by 100, as 1 Gray equals 100 rad. This tool is useful in radiation therapy, radiological protection, and exposure analysis. The formula is straightforward: Gy = rad ÷ 100.
Gray (Gy) is the SI unit for absorbed dose, while rad is often used historically or in specific contexts. Conversion is critical for standardizing data in scientific studies or medical reports. For example, 500 rad equals 5 Gy. Always ensure the measurement context (radiation type, tissue, etc.) is clear before conversion.
Apply this calculator for tasks like radiation therapy planning, occupational exposure reports, or radioprotection studies. Avoid use without understanding the measurement context, as factors like radiation energy or material density can influence the practical application of converted values.
Frequently asked questions
Why divide by 100 when converting rad to Gray?
Because 1 Gray is defined as 100 rad, an internationally standardized relation for absorbed dose measurements.
Can this calculator handle decimal values?
Yes. Simply input numbers with decimal places for accurate conversion.
What are rad and Gray used for?
Gray is the SI unit for absorbed dose. Rad is less common today but still appears in historical or specific reports.
Is this tool suitable for medical calculations?
Yes, but verify if the measurement context requires additional considerations like radiation type or biological tissue.