Cobweb (1821–1848) was an undefeated British Thoroughbred racehorse and who won two British Classic Races as a three-year-old and went on to become a highly successful broodmare. Cobweb's racing career consisted of three competitive races in the early part of 1824. After winning on her debut she claimed a second prize when her opponents were withdrawn by their owners. She then won the 1000 Guineas at Newmarket Racecourse and the Oaks Stakes at Epsom Downs Racecourse before being retired to stud.