Compton's Encyclopedia and Fact-Index is the title of an encyclopedia published in Chicago, Illinois since the 1920s. The company was founded by F. E. Compton and was acquired in the 1940s by the Encyclopædia Britannica Inc. In the creation of Encyclopædia Britannica Online (1994), the company was able to build on experience from the existing multimedia edition of Compton's Encyclopedia (1992). Since the 1990s, Compton's Encyclopedia is a product of The Learning Company, since 2001 a part of Riverdeep.

Titles, editions and sizes

• Compton's Pictured Encyclopedia, 10 volumes, 1924, 1926, 1929
  • 16 volumes, 1931
  • 15 volumes, 1932, 1937, 1938, 1940, 1945, 1949, 1950, 1951, 1953, 1956, 1957, 1958, 1962
• Compton's Encyclopedia and Fact-Index, 24 volumes 1969-1971
  • 22 volumes, 1972, 1973
  • 26 volumes, annually 1974-1978 and 1980-1995, 2004
• Compton's Family Encyclopedia, CDROM, 1990, 1991. See the inspiring article on it in 1990 Mar 19 Newsweek, p. 45.
• Compton's Multimedia Encyclopedia, CDROM, 1992
• Compton's Interactive Encyclopedia, CDROM, annually 1995-1998