🔍 reads the actual bytes — never leaves your browser
File Type Identifier
Detects a file's real type from its magic-byte signature, not its filename extension - the same trick used to spot a renamed .exe pretending to be a .jpg. Nothing is uploaded anywhere.
Click or drop a file here
How it works
The tool reads only the first 32 bytes of the selected file, locally, and compares them against a table of known magic-byte signatures — such as PNG's 0x89504E47, PDF's %PDF, or ZIP's PK\x03\x04 — to determine the file's real format regardless of what its extension claims, flagging a mismatch (like a ".jpg" that's actually a Windows .exe) as a warning.
FAQ
Why might a WebP image get identified as WAV audio instead?
Both formats begin with the same four-byte "RIFF" container header, and this tool checks its signature table in order — since WAV audio is checked before WebP, a WebP file matching that shared RIFF prefix is reported as WAV audio rather than WebP.
What happens if a file's real format isn't in the signature table at all?
It's reported as "Unknown" — only the first 32 bytes are checked against the table's known signatures, so a valid but less common file type, or plain text, won't be recognized.
Free, unlimited, no account. If this saved you a paid tool, a small thanks is appreciated.