Can this help explain a 415 Unsupported Media Type response?
Yes. Parse the exact header value first and check whether the media type, charset, or boundary is malformed or missing.
Content-Type Parser (MIME, Charset, Boundary)
Parse Content-Type headers and extract MIME parameters
API & HTTP
π 100% client-side β your data never leaves this pagePage mode
Content-Type Input
Quick CTA
Paste a Content-Type header to inspect MIME, charset, boundary, and params immediately; troubleshooting hints stay in Deep.
Output
Parsed result will appear here
100% client-side
Page reading mode
Quick keeps the summary, direct answers, and next steps so you can validate fit and get a result faster.
About this tool
Content-Type Parser helps you parse and normalize HTTP Content-Type header values in seconds. Paste one or multiple lines like application/json; charset=utf-8 or multipart/form-data; boundary=----WebKitFormBoundary and get structured output: media type, subtype, charset, boundary, plus extra parameters. It is useful when APIs fail due to malformed headers, file uploads break because of boundary issues, or clients reject responses because of incorrect content type formatting. The parser also marks invalid lines so you can quickly locate syntax mistakes before deployment. All parsing runs locally in your browser.
Direct Answers
What does boundary matter for multipart/form-data?
The server needs the boundary token to split the body into parts. Missing or mismatched boundaries often break file uploads.
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