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identify any file by its real content
build v6.0

Drop a file to identify.

or

any file type · reads the real content, not the name · batch · no upload · no signup

Reads the first bytes of a file — its signature, or "magic number" — to work out what it really is, regardless of the extension. You get the format, its MIME type, what it's typically used for, and which apps open it. If the name says one thing but the content says another, it tells you. Everything runs in this tab; your file never leaves your device.