Validationflags: i
MIME Type
Validate MIME media type strings like text/html, application/json, or image/png; charset=utf-8.
Try it in RegexPro →Available in
Pattern
regexengine-agnostic
^([a-z]+)\/([a-z0-9][a-z0-9!#$&\-^_.]*)(?:;\s*[a-z]+=\S+)*$ (flags: i)Raw source: ^([a-z]+)\/([a-z0-9][a-z0-9!#$&\-^_.]*)(?:;\s*[a-z]+=\S+)*$
How it works
Group 1 captures the primary type (text, image, application, etc). Group 2 captures the subtype using the allowed MIME subtype character set. The optional trailing group (?:;\s*[a-z]+=\S+)* matches parameters like charset=utf-8 or boundary=something.
Examples
Input
application/jsonMatches
application/json
Input
text/html; charset=utf-8Matches
text/html; charset=utf-8
Input
not a mime typeNo match
—Common use cases
- •Content-Type header validation in API middleware
- •File upload MIME type enforcement
- •HTTP response content negotiation
- •OpenAPI spec validation tooling
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