Homebrewing is the brewing of beer, wine, cider and other beverages, both alcoholic and non-alcoholic, through fermentation on a small scale as a hobby for personal consumption, free distribution at social gatherings, amateur brewing competitions or other non-commercial reasons.

People homebrew beer for a variety of reasons. Homebrewing can be cheaper than buying commercially equivalent beverages; it can allow people to adjust recipes to their own tastes (creating beverages that are unavailable on the open market, or low-ethanol beverages which may contain less calories and so be less-fattening); or people may enjoy entering homebrew competitions. Sometimes referred to as "craft brewing", homebrewing has developed various homebrewing clubs and competitions. The Beer Judge Certification Program or BJCP is an American organization which sanctions beer, mead, and cider homebrew competitions, certifies judges, and offers categories for judging; these judging categories are called "Beer Style Guidelines" and are written by the BJCP Style Committee.