AgeGuess is an on-line game that lets you guess the ages of other players as well as post your own photos for others to analyze. By participating in AgeGuess, citizen scientists create a research data set for the study of human aging.

The success of AgeGuess depends on participation. The game’s organizers request that players spend time on the site guessing other people’s ages but also upload several pictures of themselves and their family members of varying ages. Players earn points based on their guesses and can compete against other citizen scientists.