| bkmk | Internet Explorer Bookmark Data |
| bkmk | Yummy FTP Pro Bookmark |
| bkp | Steinberg WaveLab Backup Plan |
| bkr | BK ReplaceEm Fileset |
| bksln | Freescale BeeKit Solution File |
| bkt | Zortech 3 Tools Samples Data |
| bku | Sage Timeslips Backup |
| bkup | Groundspeak Wherigo Backup File |
| bkx | X-Rite eXact Manager Device Backup |
| bky | SmartWare Backup Keyboard Data |
| bkz | FileFort Backup Data |
| bla | Blaise Datamodel |
| blb | Act! Blob Data |
| blb | Treepad Database Blob Data |
| bld | Bingooo Language Definition Data |
| bld | Right-J Load Calculation Data |
| bldinp | OnScale Build Input Data |
| blend1 | Blender Document Backup |
| blend2 | Blender Document Backup |
| blf | CLFS BaseLog |
| blf | Common Log File System Binary Data |
| blf | MasterWorks Data |
| bli | Blaise Prepared Library |
| bli | LinkOne Library Data |
| blif | Berkeley Logic Interchange Format Data |
| blk | Abbyy FineReader Block Template |
| blk | Autodesk 3D Studio Max Block Library |
| blk | Autodesk AutoCAD Block Template |
| blk | Leica BLK360 Data |
| blk | Lightscape Block File |
| bll | ENVI Bad Lines List |
| blm | Envisioneer Catalog Data |
| blm | Rightmove Bulk Load Mass Data |
| bln | Golden Software Blanking |
| blo | IBM DB2 Binary Large Object Data |
