You can use these calculators to calculate electromagnetic energies, gamma activity, dose rate, radiation, and more..

Rad Pro Calculator: Free Beta Emitter Bremsstrahlung Calculator
Bremsstrahlung x-ray calculations for beta interactions.

Rad Pro Calculator: Free Online ALARA Calculator
ALARA calculations for dose and job planning.

Rad Pro Calculator: Free Online Electromagnetic Energy Inverse Square Law Calculator
Inverse Square Law calculations for electromagnetic energies.

Rad Pro Calculator: Free Online Frisker and Scan MDA/MDC Calculator
Minimum detectable concentration and contamination (MDC aka MDA) for scanners (includes LLD and critical level calculations).

Rad Pro Calculator: Free Online Gamma Activity, Dose Rate and Shielding Calculator
Gamma emitter shielding equations (with or without buildup).

Rad Pro Calculator: Free Online Radiation Scaler, Counter MDA/MDC Calculator
Minimum detectable concentration and contamination (MDC aka MDA) for counters.

Rad Pro Calculator: Free Online Radioactive Isotopes Decay Calculator
Isotope radioactive decay, timed decay and half life equations.

Rad Pro Calculator: Free Online Radiological Units Conversions
Radiological units conversion.

Rad Pro Calculator: Free Online Uranium Enrichment Calculator
Uranium enrichment from U-234 and U-238 lab data for environmental levels of uranium (also works well for uranium fuel enrichment and U enrichment in nuclear waste).

Rad Pro Calculator: Free Online Uranium Fuel Loading Calculator
Uranium fuel loading ratios.

Rad Pro Calculator: Free Online Uranium and Plutonium Specific Activity Calculator
Grams of plutonium (Pu) and uranium (U) from activity (specific activity).

Rad Pro Calculator: Free Online X-Ray, Dose-Rate and Shielding Calculator
Dose-rates for x-ray machines and devices.