Chronometry or numerical dating aims to provide age estimates in terms of years for archaeological and paleoanthropological events or processes. Most of the methods currently applied with success are based on the physical phenomenon of radioactivity, which provides the clock. Ongoing developments in the last few decades provide rapid progress in the growing field of chronometric dating. In particular, improvements in time resolution and application to novel sample materials as well as the extension of the age ranges have left a strong impact on current paleoanthropology. This contribution introduces the reader to the principles of radiometric dating. The most frequently applied dating methods, such as potassium–argon, uranium-series, luminescence, electron spin resonance, cosmogenic ²⁶Al/¹⁰Be, and radiocarbon techniques, are described. Their potential for paleoanthropology is illustrated using various examples covering the entire period since hominini entered the scene a few million years ago.