Students will use this online Radioactive Decay Calculator to compute radioactive decay, timed decay, and timed solid disposal for a databank containing 116 isotopes. This calculator also features University of British Columbia disposal limits and a unit converter and date/time calculators that calculate the half-life for selected isotopes; radioactive decay final activity, given the initial activity and decay time; the decay time, given the initial and final activities; and the decay time, given the mass of a solid and the initial activity.