List of radioactive nuclides by half-life


This is a list of radioactive nuclides, ordered by half-life from shortest to longest, in seconds, minutes, hours, days and years. Current methods make it difficult to measure half-lives between approximately 10−19 and 10−10 seconds.

10−24 seconds (yoctoseconds)

Twenty-three yoctoseconds is the time needed to traverse a 7-femtometre distance at the speed of light—around the diameter of a large atomic nucleus.

10−21 seconds (zeptoseconds)

10−18 seconds (attoseconds)

10−12 seconds (picoseconds)

10−9 seconds (nanoseconds)

10−6 seconds (microseconds)

10−3 seconds (milliseconds)

100 seconds

103 seconds (kiloseconds)

106 seconds (megaseconds)

109 seconds (gigaseconds)

1012 seconds (teraseconds)

1015 seconds (petaseconds)

1018 seconds (exaseconds)

1021 seconds (zettaseconds)

1024 seconds (yottaseconds)

1027 seconds (ronnaseconds)

1030 seconds (quettaseconds)

The half-life of tellurium-128 is over 160 trillion times greater than the age of the universe, which is seconds.