Relative age is the age of a rock layer (or the fossils it contains) compared to other layers. It can be determined by looking at the position of rock layers. Absolute age is the numeric age of a layer of rocks or fossils. Absolute age can be determined by using radiometric dating.

What is absolute fossil dating?

Unlike relative dating methods, absolute dating methods provide chronological estimates of the age of certain geological materials associated with fossils, and even direct age measurements of the fossil material itself.

What age are most fossils?

How old are fossils? The oldest known fossils are the remains of unicellular organisms dating back, about 3.4 billion years. Although most fossils are a lot younger, when talking about the age of fossils, we often tend to speak about millions, tens of millions or even hundreds of million years ago.