┌─ FILE ANALYSIS ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────── ┐
│ DEVELOPER : N/A (Universal)
│ CATEGORY : System
│ MIME TYPE : application/x-backup
└ ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────── ┘
What is a BAK file?
BAK is a generic file extension used to denote backup copies of files. Many applications automatically create .bak files before modifying originals, providing a recovery mechanism. The actual content of a BAK file mirrors the original file format — a .bak created from a .doc is still a Word document internally.
How to open BAK files
- Rename the extension — Change .bak to the original format
- Open with original application — If you know the source program
- Notepad (Windows) — Check if it is plain text
- Hex editor — Identify file type from magic bytes
Technical specifications
| Property | Value |
|---|---|
| Format | Varies (mirrors original file) |
| Created By | Applications, databases, text editors |
| Content | Exact copy of original file |
| Identification | Check file headers / magic bytes |
| Common Sources | SQL Server, AutoCAD, Notepad++ |
Common use cases
- Database backups: SQL Server .bak database backups.
- AutoCAD: Automatic drawing backup files.
- Text editors: Notepad++, Vim backup copies.
- System restore: Registry and configuration backups.