THE NUMORIX GUIDE
How to use the Radiation Converter
Last reviewed September 14, 2026
What this calculator does
The engine normalizes the input to gray and divides by the configured factors: 1 rad = 0.
Formula and method
The engine normalizes the input to gray and divides by the configured factors: 1 rad = 0.01 Gy, 1 Sv = 1 Gy in the table, 1 rem = 0.01 Sv, and 1 roentgen = 0.00877 Gy. It then presents all five values as a single conversion set.
Variables and inputs
Enter a numeric value and choose Gray, Rad, Sievert, Rem, or Roentgen. The UI continuously shows gray as the headline and every conversion to six decimals. It does not collect radiation type, particle energy, tissue, exposure geometry, or time.
Worked example
For 1 Gy, the engine returns 100 rad, 1 Sv, 100 rem, and 1 / 0.00877 = about 114.0251 roentgen. The 1 Gy = 1 Sv line is the engine's simplified equivalence, not a general dose rule.
How to interpret the result
Gray and rad describe absorbed dose, while sievert and rem describe biologically weighted equivalent or effective dose. Roentgen is an exposure unit for ionization in air. These quantities are related in specific conditions but are not interchangeable merely because the numerical factors look similar.
Common mistakes to avoid
Do not treat every gray as one sievert, or every roentgen as a universal tissue dose. Distinguish absorbed dose from equivalent dose and exposure, and do not infer health risk from a converted number without radiation type, dose rate, tissue, and context.
Assumptions and limitations
The engine uses a rough gamma-style Gy/Sv equivalence and a fixed 0.00877 Gy per roentgen factor. It does not apply radiation weighting factors, tissue weighting factors, particle energy, shielding, dose rate, biological response, or regulatory limits. Its numeric inputs are not physically validated.