The TestDaF-Institut is an institute for language testing in Hagen, Germany. It runs tests in German as a foreign language. The tests are called TestDaF, short for Test Deutsch als Fremdsprache: "Test of German as a foreign language", and are aimed at people who would like to study at German universities, academics and scientists.
The institute is part of the Society for Academic Test Development, Gesellschaft für Akademische Testentwicklung e.V., based in Bonn, which was founded in 2000 by various German-language institutions including DAAD (German Academic Exchange Service), the Goethe-Institut, the distance learning university in Hagen, and the Carl Duisberg Centre in Cologne. The idea for the society came from the DAAD and the German Rectors' Conference (Hochschulrektorenkonferenz, HRK).
The tests can be taken in 65 different countries around the world (2004). They cover listening comprehension, reading comprehension, writing and speaking, and are recognised by German universities as proof of prospective students' ability.
There are three levels (TDN 3–5) which correspond to the Common European Framework of Reference for Languages levels B2–C2.