​LettError is a pioneering type foundry established in 1989 by Dutch designers Just van Rossum and Erik van Blokland. Based in The Hague, Netherlands, the studio is renowned for its experimental approach to typography, blending design with programming to push the boundaries of type design. Their groundbreaking typeface, FF Beowolf (1990), introduced the concept of "random fonts," where each printed instance of a character could vary, challenging the notion of static letterforms. FF Beowolf was acquired by the Museum of Modern Art (MoMA) in New York as part of its permanent collection, recognizing its significance in the evolution of digital typography. LettError continues to innovate with projects like LTR NCND, a variable font inspired by classic typewriter textures, and LTR Federal, a digitization of U.S. currency engraving styles. Their work is available through platforms like Adobe Fonts and Fontstand.