Freiburg im Breisgau (German: [ˈfʁaɪbʊʁk ʔɪm ˈbʁaɪsɡaʊ] (listen); abbreviated as Freiburg i. Br. or Freiburg i. B.; Low Alemannic: Friburg im Brisgau), commonly referred to as Freiburg, is an independent city in Baden-Württemberg, Germany. With a population of about 230,000 (as of 31 December 2018), Freiburg is the fourth-largest city in Baden-Württemberg after Stuttgart, Mannheim, and Karlsruhe. The Freiburg built-up area had a population of 354,500 (2021). The population of the greater Freiburg metropolitan area ("Einzugsgebiet") was 656,753 in 2018. In the south-west of the country, it straddles the Dreisam river, at the foot of the Schlossberg.

Historically, the city has acted as the hub of the Breisgau region on the western edge of the Black Forest in the Upper Rhine Plain. A famous old German university town, and archiepiscopal seat, Freiburg was incorporated in the early twelfth century and developed into a major commercial, intellectual, and ecclesiastical center of the upper Rhine region. The city is known for its medieval minster and Renaissance university, as well as for its high standard of living and advanced environmental practices. The city is situated in the heart of the major Baden wine-growing region and serves as the primary tourist entry point to the scenic beauty of the Black Forest. According to meteorological statistics, the city is one of the warmest in Germany, and held the all-time German temperature record of 40.2 °C (104.4 °F) from 2003 to 2015.