| p4 | Perforce P4 Data |
| p4b | Pix4D 3D Textured Mesh Data |
| p4thor | Thor Exported Packet Records Data |
| p5m | PyMOL P5M Script |
| p5x | Microsoft Windows System File |
| p7a | PKCS #7 Attached Signature |
| p7b | PKCS #7 Certificate Data in Base 64 Format |
| p7c | PKCS #7 Certificate Data |
| p7d | PKCS #7 Detached Signature |
| p7e | File Encryptor Encrypted Data |
| p7f | digiSeal Reader P7F Data |
| p7m | PKCS #7 Encrypted Message |
| p7mkey | KeePass Certificate-protected Key |
| p7r | PKCS #7 Certificate Request Response File |
| p7s | PKCS #7 Digital Signature |
| p7x | Windows SDK Packed Digital Signature |
| p7z | PKCS #7 Compressed Message |
| p8 | PICO-8 Data |
| p83 | GAEB DA 2000 Data File |
| p99 | MicroStation Modification Project Resource File |
| pa1 | PageAhead Work Table Data |
| pa2 | CME SPAN Expanded Format Data |
| pa2m | SAM PA2M Alignment Data |
| pa4 | Vector NTI Protein Archive |
| paa | Personal Ancestral File Data |
| pab | Microsoft Outlook Personal Address Book |
| pack | CustoPack Tools Theme Pack |
| pad | Act! Database Pointer |
| pad | Portable Application Description |
| pad | Top Secret Crypto Gold One Time Pad Data |
| pad | Visual Expert Application Layout Data |
| padfx | Metrel SDK Data Structure |
| padl | Cakewalk Pyro Audio Creator Disk Layout |
| paf | Personal Ancestral File Data |
| pafsc | Esko LinkEdge Package |
