Most of the isotope data on this site has been obtained from the National Nuclear Data Center.
Naturally Occurring Isotopes
| Mass Number | Natural Abundance | Half-life |
| 40 | 96.94% | > 3.0×10+21 years |
| 42 | 0.647% | STABLE |
| 43 | 0.135% | STABLE |
| 44 | 2.09% | STABLE |
| 46 | 0.004% | > 0.28×10+16 years |
| 48 | 0.187% | > 5.8×1022 years |
Known Isotopes
| Mass Number | Half-life | Decay Mode | Branching Percentage |
| 34 | < 35 nanoseconds | Proton Emission | No Data Available |
| 35 | 25.7 milliseconds | Electron Capture with delayed Proton Emission | 95.90% |
| Electron Capture with delayed Double Proton Emission | 4.10% | ||
| Electron Capture | 100.00% | ||
| 36 | 102 milliseconds | Electron Capture | 100.00% |
| Electron Capture with delayed Proton Emission | 54.30% | ||
| 37 | 181.1 milliseconds | Electron Capture | 100.00% |
| Electron Capture with delayed Proton Emission | 82.10% | ||
| 38 | 440 milliseconds | Electron Capture | 100.00% |
| 39 | 859.6 milliseconds | Electron Capture | 100.00% |
| 40 | > 3.0×10+21 years | Double Electron Capture | No Data Available |
| 41 | 1.02×10+5 years | Electron Capture | 100.00% |
| 42 | STABLE | - | - |
| 43 | STABLE | - | - |
| 44 | STABLE | - | - |
| 45 | 162.61 days | Beta-minus Decay | 100.00% |
| 46 | > 0.28×10+16 years | Double Beta-minus Decay | No Data Available |
| 47 | 4.536 days | Beta-minus Decay | 100.00% |
| 48 | > 5.8×1022 years | Double Beta-minus Decay | 75.00% |
| 49 | 8.718 minutes | Beta-minus Decay | 100.00% |
| 50 | 13.9 seconds | Beta-minus Decay | 100.00% |
| 51 | 10.0 seconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | No Data Available | ||
| 52 | 4.6 seconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | <= 2.00% | ||
| 53 | 90 milliseconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | > 30.00% | ||
| 54 | 86 milliseconds | Beta-minus Decay | 100.00% |
| 55 | 22 milliseconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | No Data Available | ||
| 56 | 11 milliseconds | Beta-minus Decay | No Data Available |
| Beta-minus Decay with delayed Neutron Emission (suspected) | No Data Available | ||
| 57 | > 620 nanoseconds | Beta-minus Decay with delayed Double Neutron Emission | No Data Available |
| Beta-minus Decay | No Data Available | ||
| Beta-minus Decay with delayed Neutron Emission | No Data Available | ||
| 58 | > 620 nanoseconds | Beta-minus Decay | No Data Available |
| Beta-minus Decay with delayed Neutron Emission | No Data Available |
This page is maintained by Steve Gagnon.