MIME Type Checker
Enter a filename you are about to serve and get the Content-Type it should carry, plus the byte signature the conclusion came from.
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Your file is read and processed inside your own browser. It is never uploaded to our server, and it still works with the network unplugged.
How It Works
- Choose — Pick or drop your file into the area above. It stays on your machine unless this tool says otherwise.
- Configure — Set the options that appear once the file is read.
- Run — Press the action button and wait for the result.
- Take it — Download the output, or copy the result if the tool prints one.
Frequently Asked Questions
How is the file type detected?
By reading the first bytes of the file and matching them against known signatures, then comparing that with the extension you happen to have. A file renamed to .jpg that starts with %PDF is reported as the mismatch it is.
Is the file uploaded?
No. Only the leading bytes and the metadata the browser already exposes are read, locally, through the File API.