| .br7 |
Bryce 7 Scene File |
| .blp |
Blizzard Texture File |
| .brg |
Age of Mythology Model File |
| .blf |
Binary logging format file, Common Log File System |
| .bblm |
BBEdit Language Module |
| .bbb |
BlackBerry Mobile Phone Backup File |
| .blend1 |
Blender Document Backup File |
| .bit |
FinalCrypt Encrypted Data File |
| .beam |
Compiled Erlang File |
| .b1 |
B1 Compressed Archive |
| .brn |
BrainStorm Data File |
| .blogthis |
Windows Live Writer Data File |
| .bdt3 |
BEEDOCS Timeline 3D 3 Document |
| .bmz |
Portal Bonus Map Zip File |
| .bvd |
Bitdefender Vault File |
| .bio |
BIOS File |
| .bss |
Resident Evil Background Images File |
| .bay |
Casio RAW Image |
| .bcl |
Illumina Base Call File |
| .bpn |
ArchiCAD Project Backup File |
| .bpd |
Business Plan Pro Document |
| .btd |
Business-in-a-Box Document |
| .bxl |
Accelerated Designs PCB Library File |
| .bkz |
FileFort Backup File |