Carbon tetrachloride, also known by many other names (the most notable being carbon tet in the cleaning industry, and as Halon or Freon in HVAC; see Table for others) is the organic compound with the formula CCl₄. It was formerly widely used in fire extinguishers, as a precursor to refrigerants, and as a cleaning agent. It is a colourless liquid with a "sweet" smell that can be detected at low levels.

Both carbon tetrachloride and tetrachloromethane are acceptable names under IUPAC nomenclature.

The production of carbon tetrachloride has steeply declined since the 1980s due to environmental concerns and the decreased demand for CFCs, which were derived from carbon tetrachloride. In 1992, production in the U.S.-Europe-Japan was estimated at 720,000 tonnes.

Carbon tetrachloride was originally synthesised by the French chemist Henri Victor Regnault in 1839 by the reaction of chloroform with chlorine, but now it is mainly produced from methane:

The production often utilizes by-products of other chlorination reactions, such as from the syntheses of dichloromethane and chloroform. Higher chlorocarbons are also subjected to "chlorinolysis:"