The University of Oxford is a research university with a collegiate structure, based in the city of Oxford in the United Kingdom. No founding charter survives and its precise date of establishment is not known; the earliest records instead show that teaching was already taking place at Oxford by 1096, the year conventionally given as its origin. On that basis it is treated as the oldest degree-granting institution anywhere in the English-speaking world, and the second-oldest still operating without interruption. Growth accelerated after 1167, when Henry II barred English scholars from studying in Paris, and a violent dispute with the townspeople in 1209 drove part of the academic community northeast, where it went on to found Cambridge.

The university operates as a federation of 43 colleges, permanent private halls and societies, set alongside faculties and departments that are grouped into four academic divisions covering the humanities, the social sciences, medical sciences, and the mathematical, physical and life sciences. Colleges admit and accommodate their own members and deliver much of the small-group teaching, while the divisions and departments run lectures, laboratory work, examinations and most graduate provision. Undergraduate study is organised around the tutorial, in which students discuss written work with an academic individually or in pairs. Enrolment stood at 26,800 in 2025, of whom 12,460 were undergraduates and 13,755 postgraduates, supported by roughly 8,005 academic staff.

Research activity extends across all four divisions and accounted for 801.3 million pounds of the university's 3.02 billion pound consolidated income in the financial year ending July 2025. Supporting institutions include the Bodleian Libraries, the largest academic library system in the country, the Ashmolean Museum, which is the oldest university museum in the world, and Oxford University Press. There is no central campus: colleges, departments, laboratories, libraries and museums are dispersed through the centre of Oxford and its surrounding districts, some 75 kilometres northwest of London, leaving university buildings interleaved with the ordinary fabric of the town.