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npm · #320 most downloaded on npm
Parses, serializes, and manipulates MIME types, according to the WHATWG MIME Sniffing Standard
Last release 8 months ago
20 Jan 2026
Release timing varies
gaps range from 2 months to 2.8 years
Nearly every release is documented
notes for 8 of 8 stable releases
Nothing withdrawn
no release was ever pulled
9 years old
8 releases · first in 2017
Node.js v20 is now the minimum supported version.
Node.js v20 is now the minimum supported version.
The MIMEType class has moved from being the default export to being a named export.
Added MIME sniffing functionality, via the computedMIMEType export.
Removed the raw parsing/serialization APIs.
Node.js v18 is now the minimum supported version.
Node.js v18 is now the minimum supported version.
Node.js v12 is now the minimum supported version.
One column per quarter.
Node.js v12 is now the minimum supported version.
Changed the semantics of the isJavaScript() method to allow parameters by default, like the other testing functions and matching the spec definition of JavaScript MIME type. Now you can prohibit parameters by using isJavaScript({ prohibitParameters: true }).
Spec update: use HTTP whitespace instead of ASCII whitespace while parsing, per https://github.com/whatwg/mimesniff/commit/126286ab2dcf3e2d541349ed935
Spec update: use HTTP whitespace instead of ASCII whitespace while parsing, per https://github.com/whatwg/mimesniff/commit/126286ab2dcf3e2d541349ed93539a88bf394ad5. In practice this means U+000C FF characters are no longer treated specially in parsing.
Spec update: use HTTP whitespace instead of ASCII whitespace while parsing, per whatwg/mimesniff@126286a. In practice this means U+000C FF characters are no longer treated specially in parsing.
Spec update: allowed empty string parameter values, per https://github.com/whatwg/mimesniff/commit/190c18af1d81754ff298cfb6fc9e581afdce4d2c.
Spec update: allowed empty string parameter values, per https://github.com/whatwg/mimesniff/commit/190c18af1d81754ff298cfb6fc9e581afdce4d2c.
Spec update: allowed empty string parameter values, per whatwg/mimesniff@190c18a.
Added static MIMEType.parse() factory, to better serve cases where you are parsing unrestricted input strings.
Added static MIMEType.parse() factory, to better serve cases where you are parsing unrestricted input strings.
Added an isJavaScript({ allowParameters }) method for checking if a MIME type is a JavaScript MIME type. (@bmeck)
Corrected the README examples to use the correct new package name, instead of the old one. (@mesaugat)
Corrected the README examples to use the correct new package name, instead of the old one. (@mesaugat)
Renamed the package from "content-type-parser" to "whatwg-mimetype", as MIME type is the more general concept, and this is now implementing part of th
Renamed the package from "content-type-parser" to "whatwg-mimetype", as MIME type is the more general concept, and this is now implementing part of the WHATWG MIME Sniffing Standard.
Replaced the parser and serializer with the newly-specified one from whatwg/mimesniff@cc81ec4.
Overhauled the API to more or less match what is proposed in whatwg/mimesniff#43. Notably, the invariants of the MIME type model are now maintained more aggressively, and the parameters exist on a separate Map-like data structure. Also removed the isText() method, as it's much less interesting than the other two.
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