Frac may refer to:
- In geology, a frac refers to fractures in a rock formation; see Fracture (geology) for natural fractures
- Hydraulic fracturing (also called "fracking"), a method for artificially creating fractures in order to extracting oil, natural gas, and other liquids or gasses.
- FRAC Act, proposed United States legislation (2009) related to hydraulic fracturing
- Frac trailer, a type of tank semi-trailer typically used during hydraulic fracturing
- Fractional part, a mathematical function
- Fungicide Resistance Action Committee, a committee for fungicide management
- Frac Press, an imprint of VDM Publishing devoted to the reproduction of Wikipedia content
- FRAK Mutual Fund Ticker of Van Eck Market Vectors ‘’Unconventional Oil & Gas‘’ ETF