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File Magic Bytes Reference
Browse file signatures (magic bytes) to identify file types from their hex headers. Search by extension, hex signature, or description.
Magic Bytes Reference
- Browse the table — All known magic bytes signatures are displayed in a searchable table.
- Search — Type an extension (.pdf, .zip), hex bytes (50 4B 03 04), or description to filter results.
- Filter by category — Use the dropdown to narrow results to a specific category (Image, Archive, Video, etc.).
What are magic bytes?
Magic bytes (also called file signatures or magic numbers) are the first few bytes of a file that uniquely identify its format. Operating systems and applications use these bytes to determine file type when the extension is missing or incorrect.
What does "Offset" mean?
The offset is the byte position where the signature begins. Most signatures start at offset 0 (the very beginning of the file), but some formats have their identifier at a fixed position later in the file.
How can I use this information?
You can use magic bytes to: identify a file with a missing or incorrect extension, verify file integrity, recover file type information from corrupted files, or understand the file format structure.
How do I view a file's hex bytes?
You can use a hex editor (like HxD, 010 Editor, or Hex Fiend) or use command-line tools like xxd or hexdump on Linux/macOS to view the raw bytes of a file.
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