Radiocarbon dating, or carbon-14 dating, is a scientific method that can accurately determine the age of organic materials as old as approximately 60,000 years. First developed in the late 1940s at the University of Chicago by Willard Libby, the technique is based on the decay of the carbon-14 isotope.

Traditional radiocarbon dating is applied to organic remains between 500 and 50,000 years old and exploits the fact that trace amounts of radioactive carbon are found in the natural environment. Now, new applications for the technique are emerging in forensics, thanks to research funded by NIJ and other organizations.

The method's true-positive rate ranges from 20–90%, with the most realistic rates being between 30 and 50%. The method's false positive error rate is approximately 10%. Increasing the number of radiocarbon dates used to date the time-series above five had no noticeable effect on the true- or false-positive rates.

With the dawn of the Industrial Age, humans began emitting much more carbon dioxide, diluting the amount of radiocarbon in the atmosphere. Nuclear testing affects radiocarbon levels, too, and dramatically increased carbon-14 levels starting in the 1950s.