| pk8 | PKCS8 Data |
| pka | Cisco Packet Tracer Activity File |
| pkb | Blackberry Password Keeper Encrypted Backup |
| pkb2 | Blackberry Password Keeper Encrypted Backup |
| pkc | Jython JAR Cache |
| pkcs12 | PKCS #12 Data File |
| pkcs7 | PKCS #7 Certificate Data |
| pkd | Eurotherm Encrypted Hydra History Data |
| pkf | Adobe Audition Peak File |
| pkg | DataFlex Compiled Package |
| pkgmeta | Bukkit Package Metadata |
| pkgx | Microsoft UE-V PKGX Data |
| pki | LibVirt PKI Data |
| pkj | PokerJuice Data |
| pkk | PuTTY Private Key |
| pkl | Migration Wizard Packing List File |
| pklg | Wireshark Packetlogger Data |
| pkn | Microsoft SMS Package Creation Notification |
| pkr | PGP Public Keyring File |
| pks | STOE Powder Diffraction Peak Data |
| pkt | Cisco Packet Tracer Network Simulation Model |
| pkt | EtherPeek Collected Packets Data |
| pku | FidoNet Batched Newsgroup Data |
| pkw | CabnetWare Package |
| pky | PockeTTY Security Certificate |
| pl3 | Harvard Graphics ChartXL Palette Data |
| pl3 | Pathloss Link Design Data |
| pl4 | Micrografx Designer 4.0 Palette |
| pl4 | Pathloss Link Design Data |
| pl5 | Pathloss Link Design Data |
