File Type Detector & Hex Viewer

Find out what a file really is. The tool reads the file’s signature — the first bytes that identify its true format — instead of trusting the extension, and shows you the raw bytes in a hex view.

Read the guide: How to Identify an Unknown File Type
File Type Detector & Hex Viewer

Drop a file here, or click to browse

Inspected entirely in your browser — nothing is uploaded.

How it works

  1. 1

    Drop any file

    Add a file with a missing, wrong or unknown extension.

  2. 2

    See its true type

    The real format is identified from the file signature, with the matching MIME type and extension.

  3. 3

    Inspect the bytes

    Scroll the hex viewer to read the raw contents alongside the decoded text.

Instant & 100% private — nothing is uploaded

Everything runs locally in your browser. Your files are processed on your own device and are never sent to a server, so there are no upload waits, no size limits from us, and nothing is ever stored or logged.

Frequently asked questions

How can it tell the type without a file extension?
Most formats begin with a known signature, a fixed sequence of bytes sometimes called a magic number. The tool matches those bytes against a catalogue of formats, so a renamed or extension-less file is still identified correctly.
Why does the detected type differ from the extension?
Extensions can be wrong or deliberately changed. When the signature and extension disagree, the signature is the reliable answer. That mismatch is also a useful warning sign for a suspicious file.
What is the hex viewer for?
It shows the raw bytes of the file as hexadecimal next to their text characters, which is handy for spotting headers, embedded strings or corruption.
Is my file sent to a server?
No. Everything runs locally in your browser. Your file is read and processed on your own device, nothing is uploaded, and nothing is logged or stored.