Absorbed Dose Converter - Gray to Rad (Gy to rad

Absorbed Dose (D), Grays, Rads & Deposited Energy Metrology

Absorbed Dose measures the physical ionizing energy deposited by radiation per unit mass of matter:

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• Universal Absorbed Dose Conversion Formulas (SI & Traditional Standards)**:

1 Gray (Gy) = 100 Rads (rad) = 1 J/kg = 1,000 mGy = 10^6\ μGy = 10,000 erg/g

1 Rad (rad) = 0.010 Gray (Gy) = 10 mGy = 10,000\ μGy = 100 erg/g = 1,000 mrad

1 Milligray (mGy) = 0.10 rad = 100 mrad = 1,000\ μGy = 10^-3 Gy

1 Kilogray (kGy) = 1,000 Gy = 100,000 rad = 100 krad | 1 erg/g = 10^-4 Gy = 0.01 rad

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• Energy Imparted & Equivalent Dose Equations**:

E = D × m (Total Physical Energy Deposited in Joules, J)

H = D × w_R (Equivalent Biological Dose in Sieverts, Sv)

1 calorie = 4.184 Joules (J)

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• Standard Absorbed Dose Benchmarks**:

• Screening Mammography: 1.50 mGy = 150.0 mrad Mean glandular breast dose

• Chest Diagnostic CT: 10.0 mGy = 1.0 rad = 10,000\ μGy Standard lung CT

• Radiotherapy Daily Fraction: 2.00 Gy = 200.0 rad Linac beam fraction

• Curative Tumor Treatment: 60.0 Gy = 6,000.0 rad 30 fractions of 2 Gy

• Industrial Food Irradiation: 1.00 kGy = 100,000 rad = 100 krad Phytosanitary pathogen control

How to Use This Calculator

Enter your Absorbed Dose Magnitude (D) (e.g. 2.0 in D), From Absorbed Dose Unit — choose from Grays (Gy = 1 J/kg = 100 rad - SI Standard), Milligrays (mGy = 10⁻³ Gy = 100 mrad - Diagnostic Radiology), Micrograys (µGy = 10⁻⁶ Gy = 0.1 mrad), To Absorbed Dose Unit — choose from Rads (rad), Grays (Gy), Milligrays (mGy), Irradiated Target Mass (kg) (e.g. 70.0 for whole body, 1.5 for organ in kg), Radiation Quality Factor (w_R) (e.g. 1.0 for Photons/Electrons, 20 for Alpha in w_R), and Radiology & Radiation Therapy Benchmark — choose from Custom Absorbed Dose, Screening Mammography Mean Glandular Dose (1.50 mGy = 150.0 mrad), Chest Diagnostic CT Scan Organ Dose (10.0 mGy = 1.0 rad). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Multipliers to SI Base Unit Gray (Gy = 1 J/kg)

Worked Example

A radiation therapist converts a legacy radiation oncology prescription of 200 rads per fraction into 2.0 Grays for the linear accelerator's computerized delivery system, preventing 100-fold dosage errors.

Understanding Your Result

Unit conversions are exact by definition within a given measurement system (e.g., 1 km = exactly 1,000 m). Cross-system conversions (metric to imperial) use defined exchange factors: 1 inch = exactly 2.54 cm; 1 pound = 0.45359237 kg. Round your converted result to match the precision of your original measurement — expressing more decimal places than your input justifies implies false accuracy. For regulatory, legal, or safety-critical applications, verify which measurement system is required by the applicable standard.