Enter a URL to check its Content-Type header and validate against file extension.
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Check any URL's Content-Type header and validate it against the file extension. Incorrect MIME types can cause browsers to mishandle files, break downloads, or create security vulnerabilities.
Enter a URL to instantly verify the MIME type, check IANA registration status, and detect Content-Type mismatches. Essential for developers debugging file serving issues.
Frequently Asked Questions
- What is Content-Type?
- Content-Type is an HTTP header that tells browsers the MIME type and character encoding of a response. It determines how browsers render or handle the content.
- Why does Content-Type matter?
- Wrong Content-Type headers can cause browsers to download instead of display files, break JavaScript execution, or trigger security warnings. Search engines and LLMs may also misinterpret content and caching behavior.
- What is a MIME type?
- MIME types (like text/html, image/png, application/json) identify file formats. They're registered with IANA and used in the Content-Type header.
Disclaimer
This website is developed by technical SEO consultant and ex-Google engineer Fili.
Bugs will happen and despite best efforts to maintain the code base and data quality, no guarantees can and/or will be given. Data may be incomplete, lost and/or errors may occur. This is a personal website and for-fun project. Use at your own risk.