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Identify a file by its magic bytes

A file with no extension, or the wrong one? Most formats start with a known signature. Open the file to see its type and the bytes that give it away.

Identify a file

How to do it

1. Drop the file on the page.
2. Read the Type line: it names the format from the file's first bytes, or says text or binary.
3. Look at the first row of the hex column to see the signature itself, such as 25 50 44 46 for a PDF.
4. Rename the file with the right extension and open it in the app it belongs to.

Your files stay on this device: Hex Editor runs in your browser, with no upload, no account and no watermark.

Questions

Which formats are recognised?

Common ones such as PNG, JPEG, GIF, WebP, PDF, ZIP, ELF and Windows MZ (.exe) programs, WAV, MP4 and SQLite. Anything else is shown as text or binary.

Can a file fake its type?

The signature is only the first few bytes, so it tells you the format a file claims to be, not whether it is safe. Be careful with programs from unknown senders.

Is the file uploaded?

No. Only your browser reads it, and the file is not run.

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