Radioactive Decay Calculator

Calculate radioactive decay to determine the remaining activity on a desired date and/or the date the activity will be reached.

When you enter a desired data, the calculator determines the activity remaining on that date. When you enter the Decay to Given Activity, the calculator determines the date when that activity will be reached. You may also enter both the date and activity.

Isotope/Radionuclide
Quantity of radioactivity measured at Assay Time
Unit of radioactivity measured at Assay Time
Date/Time of radioactivity assay
Date for which radioactivity level is desired
Radioactivity amount for which date is desired.