The Newgate Calendar serves as a comprehensive historical record of the criminal proceedings and executions conducted at Newgate Prison in London during the 18th and 19th centuries. The text functions as a moralizing chronicle, documenting the lives, crimes, and final confessions of notorious offenders to illustrate the consequences of vice and the efficacy of the British judicial system. It provides a window into the social anxieties and legal standards of the era through the lens of public punishment.

Historians frequently cite this work as a primary source for understanding the development of the British penal system and the cultural fascination with crime in the Georgian and Victorian eras. Readers often note the archaic, didactic tone of the prose, which reflects the specific moral climate of the time in which it was compiled.