Friedrich Müller may refer to:

• Maler Müller (Friedrich Müller, 1749–1825), German painter and poet
• Friedrich Christoph Müller (1751–1808), theologian and cartographer in Schwelm
• Max Müller (Friedrich Maximillian Müller, 1823–1900), German philologist and indologist
• Friedrich Konrad Müller (1823–1881), German poet, journalist and physician
• Friedrich Müller (linguist) (1834–1898), Austrian linguist
• Friedrich von Müller (1858–1941), German physician
• Friedrich W. K. Müller (1863–1930), German scholar of oriental cultures and languages
• Friedrich Mueller, also known as Eugen Sandow (1867–1925), German bodybuilder
• Friedrich-Wilhelm Müller (1897-1947), German World War II General
• Friedrich Müller (footballer) (1907–1978), German international footballer of the 1930s
• Friedrich-Karl "Tutti" Müller (1916–1944), German World War II fighter pilot

• Calixtus (disambiguation)
• Calizas de la huergina formation
• Calizas de La Huérguina Formation
• Calizas de Lychnus Formation
• Calizas y margas de Xert Formation
• Cali≠gari
• Cal Jam
• Cal Jam II
• Cal J. Bowman
• Caljobs
• CalJOBS
• Caljobs.ca.gov
• Cal johnson
• Cal Johnson (stuntman)
• Calkain
• Calkain Companies
• Calkarasi
• Cal Karasi
• Calke
• Calke, Derbyshire
• Calke Priory
• Calkin Glacier
• Calkini
• Calkini Municipality
• Calkinsia