With absolute age dating, you get a real age in actual years. Its based either on fossils which are recognized to represent a particular interval of time, or on radioactive decay of specific isotopes.

What is absolute dating in simple terms?

Absolute dating is the process of determining an age on a specified chronology in archaeology and geology. Absolute dating provides a numerical age or range, in contrast with relative dating, which places events in order without any measure of the age between events.