SAFE as an acronym may refer to:

• Safe Affordable Fission Engine, a series of small experimental nuclear reactors designed by NASA
• SAFE (organisation), Save Animals From Exploitation, a New Zealand animal advocacy organisation
• Scaled Agile Framework, a process framework for running Agile software development projects at scale
• Securing Adolescents From Exploitation-Online Act of 2007, an American law on child pornography
• Security and Freedom Ensured Act, an American law that amended the PATRIOT Act
• SAFE-BioPharma Association, Signatures and Authentication For Everyone, a pharmaceutical database
• Society of Aviation and Flight Educators, a professional aviation organization
• SAFE (cable system), South Africa Far East cable, an underwater communications cable linking South Africa and Malaysia
• State Administration of Foreign Exchange, an agency of the Chinese government
• Strategic Action For Emergencies, a fictional group to counter S.H.I.E.L.D. in Marvel Comics
• Stroke Alliance for Europe, a coalition of charities that support stroke survivors
• SAFE (Struggle Against Financial Exploitation), a UK Parliamentary Working Group who campaign against financial fraud and deception
• Survivor Activating Factor Enhancement, a metabolic pathway
• Synchronized Armed Forces Europe, the concept of synchronising of the European military forces

A safe (also called a strongbox or coffer) is a secure lockable box used for securing valuable objects against theft and/or damage from fire. A safe is usually a hollow cuboid or cylinder, with one face being removable or hinged to form a door. The body and door may be cast from metal (such as steel) or formed out of plastic through blow molding. Bank teller safes typically are secured to the counter, have a slit opening for dropping valuables into the safe without opening it, and a time-delay combination lock to foil robbers. One significant distinction between types of safes is whether the safe is secured to a wall or structure or if it can be moved around. A less secure version (only suitable for petty cash) is usually called a cash-box.