Radiation Dose and Activity Converter (Sieverts, Rem, Gray, Rad, Becquerel, Curie

Nuclear Physics & Radiation Dosimetry Metrology

Radiation measurement is divided into three distinct physical domains:

• Radioactivity / Source Decay (Becquerel & Curie): The rate of nuclear disintegrations per second, .

• Absorbed Physical Dose (Gray & Rad): The energy deposited by radiation per unit mass of matter).

• Equivalent / Biological Dose (Sievert & Rem): The absorbed dose weighted by radiation biological effectiveness (W_R) to quantify human cancer and health risks).

How to Use This Calculator

Enter your Radiation Measurement Category — choose from Equivalent / Biological Dose (Sievert, Rem, mSv, mrem), Absorbed Physical Dose (Gray, Rad, mGy), Radioactivity / Decay Rate (Becquerel, Curie, Bq, Ci), Radiation Value (e.g. 1), Dose Unit (for Biological / Absorbed) — choose from Millisieverts (mSv, 1/1000 Sv), Sieverts (Sv, Base SI), Microsieverts (µSv, 10⁻⁶ Sv), and Activity Unit (for Radioactive Decay) — choose from Becquerels (Bq, 1 decay/sec), Megabecquerels (MBq, 10⁶ Bq), Gigabecquerels (GBq, 10⁹ Bq). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Universal radiological dosimetry and radioactivity conversion formulas: to Rem: 1 Sievert (Sv) = 100 Rem, 1 mSv = 100 mrem to Rad: 1 Gray (Gy) = 100 Rad = 1 Joule/kg Dose: H (Sv) = D (Gy) × W_R (W_R = 1 for Gamma/X-ray/Beta): 1 Curie (Ci) = 3.7 × 10^10 Becquerels (Bq) = 37 GBq

Worked Example

For example, converting a 1.0 mSv (millisievert) medical diagnostic exposure: 100.0 mrem, 0.100 rem, 0.001 Gray, and 0.100 Rad. This is equivalent to approximately 10 standard chest X-rays (0.1 mSv each) and represents about one-third of average natural annual background radiation.

Understanding Your Result

Unit conversion precision: round to the same number of significant figures as your original measurement. Converting 6 feet to meters gives 1.8288 m — but if your measurement was approximate (±1 inch), expressing more than 2 decimal places is false precision. For international trade and technical specifications, SI units (meters, kilograms, liters) are the standard. US customary units (feet, pounds, gallons) differ from Imperial UK units: 1 US gallon = 3.785 L vs. 1 UK gallon = 4.546 L.