| bctpuri | Vuze BCTP URI Data |
| bcuri | BitComet URI Data |
| bcx | Beam-Report Standard Definition Data |
| bcz | Siemens Teamcenter Zipped Briefcase File |
| bd2 | Lacerte Tax Data |
| bd3 | Lacerte Tax Data |
| bd4 | Bridge Designer 4 Data |
| bdb | Blaise Database |
| bdb2 | Skillpipe Reader Course Data |
| bdct | BBEdit Dictionary Data |
| bdd | CARA Sound Radiation Data |
| bde | PTC Creo BDE File |
| bdf | SmartWare Backup Definition Data |
| bdf | Oasys T/HIS Bulk Data File |
| bdg | Badge Designer 2000 Data |
| bdi | PTC Creo BDI File |
| bdic | Google Chrome Dictionary |
| bdm | Blaise Data Model |
| bdm | PTC Creo BDM File |
| bdmv | Blu-ray Disc Information File |
| bdoc | DigiDoc BDOC Digital Signature |
| bdp | Microsoft Exchange Non-Delivery Report Bad Mail Pointer |
| bdr | Microsoft Exchange Non-Delivery Report Body |
| bdsdeploy | Borland Developer Studio Deployment Data |
| bdt | Beedocs Timeline 3D Document |
| bdt2 | Beedocs Timeline 3D Document |
| bdt3 | Beedocs Timeline 3D Document |
| bdv | Blaise Dataview File |
| bdw | Budget for Windows Data |
| bdy | DMAP Boundary Data |