people can identify up to 10,000 faces, scientists have discovered. In the first study of its kind, researchers quantified the number of faces an individual human can know—and findings showed people were able to recognize between 1,000 and 10,000, with the average being 5,000 faces.

The research, published in Proceedings of the Royal Society B: Biological Sciences, was carried out by Rob Jenkins, from the Department of Psychology at the University of York, and colleagues.