| phl | Icon Phile Scheme |
| phm | Pro Home Manager Data |
| pho | MBROLA Phonetic Data |
| phoa | PhoA Album |
| photolibrary | Apple iPhoto Photo Library |
| phr | Adobe RoboHelp Phrase List |
| phred | Phred Data |
| phs | XtalView Xfit Phase Data |
| pht | ParaView Phasta Metafile |
| phu | PicoQuant Time Tagged File |
| phw | PhotoWebber Session Data |
| phy | PHYLIP Format |
| phylip | PHYLIP Data |
| physfs | PhysicsFS Data |
| pi | iPi Calculation Data |
| pib | Platform Independent Binary |
| picd | ProfiCAD Integrated Circuit Document |
| picon | Dreambox Picon File |
| pidb | MonoDevelop Parser Information Database |
| pigm | Indigo Packed Material Data |
| pigs | Indigo Renderer Packaged Scene |
| pik | Protel 99 Pick and Place Data |
| pike | Pike Source Code |
| pin | BLAST Protein Database |
| piw | PI ProcessBook Data |
| pix | SmartWare Physical Index |
| pj | Project64 Saved State File |
| pj1 | Project64 Saved State File |
| pj2 | Project64 Saved State File |
| pjb | IBM InfoSphere Information Server Manager Data |
| pjd | Portfolio Exported Categories Data |
| pjf | Photojunction File |
| pjf | iAddress Postal Job File |
| pjl | HP Printer Job Language Data |
| pjnz | Spectrum Projection Data |