| Isotopes of Berkelium | 
|  Notes | 
| Berkelium has no stable isotopes. | 
|  Notable Isotopes  | 
|  245Bk [148 neutrons] | 
|  Abundance: synthetic | 
|  Half life: 4.94 days [ Electron Capture ] | 
|  Decay Energy: 0.810 MeV | 
|  Decays to 245Cm. | 
|  Half life: 4.94 days [ Alpha Decay ] | 
|  Decay Energy: 6.455 MeV | 
|  Decays to 241Am. | 
|  246Bk [149 neutrons] | 
|  Abundance: synthetic | 
|  Half life: 1.8 days [ Alpha Decay ] | 
|  Decay Energy: 6.070 MeV | 
|  Decays to 242Am. | 
|  Half life: 1.8 days	[ Electron Capture ] | 
|  Decay Energy: 1.350 MeV | 
|  Decays to 246Cm. | 
|  247Bk [150 neutrons] | 
|  Abundance: synthetic | 
|  Half life: 1380 years [ Alpha Decay ] | 
|  Decay Energy: 5.889 MeV | 
|  Decays to 243Am. | 
|  248Bk [151 neutrons] | 
|  Abundance: synthetic | 
|  Half life:  9+ years [ Alpha Decay ] | 
|  Decay Energy: 5.803 MeV | 
|  Decays to 244Am. | 
|  249Bk [152 neutrons] | 
|  Abundance: synthetic | 
|  Half life: 320 days [ Alpha Decay ] | 
|  Decay Energy: 5.526 MeV | 
|  Decays to 245Am. | 
|  Half life: 320 days | 
|  Decay Energy: ? MeV | 
|  Decays to ?. | 
|  Half life: 320 days [ beta- ] | 
|  Decay Energy: 0.125 MeV | 
|  Decays to 249Cf. |