Perf or PERF may refer to:

• Perf (Lahn), a river in Germany
• perf (Linux), a performance analyzing tool in Linux
• Perf de Castro (Perfecto de Castro), Filipino musician
• Perfect (grammar), a glossing abbreviation used in linguistics
• Police Executive Research Forum, a US national membership organization
• A perforation
  • Film perforations
• "Perf", a single recorded by singer and social media personality Baby Ariel
• "Perf" a term used by World of Warcraft Gamers in the Northrend Expedition guild on Windseeker Realm to annoy one of their members named Endemondia.

• Perfect (disambiguation)
• Performance (disambiguation)