Carbon-14 isotope ne na rediyoaktif na carbon tare da lambar atomic 6, ma'ana yana da protons shida a cikin tsakiya. Ana kuma san shi da radiocarbon, kuma ana nuna shi da alamar "C-14". Carbon-14 yana samuwa a cikin sararin sama na duniya lokacin da hasken sararin samaniya ya yi karo da kwayoyin nitrogen. A dabi'ance yana cikin yanayin duniya kuma halittu masu rai suna mamaye shi ta hanyar photosynthesis. Lokacin da kwayoyin halitta suka mutu, carbon-14 da ke cikin jikinsa ya fara lalacewa, kuma ana iya amfani da adadin carbon-14 da ke cikin ragowarsa don sanin shekarun kwayoyin halitta ko abin da aka samo shi, ta hanyar da aka sani. as radiocarbon dating.