# Feed HTML - an HTML subset for RSS readers

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By Tim, November 9, 2026 at 14:10 UTC.
Web version: https://twowavesandadot.blog/feed-html-an-html-subset-for-rss-readers.html

I have set up a second RFC: [Feed HTML](https://twowavesandadot.blog/rfc/Downread-RFC-2-HTML-Subset-for-Feed-Content.html) defines an HTML set for RSS readers and similar applications. 

This addresses a long-standing issue with RSS: it allows HTML, but no one defines which HTML features you can use. Many simple RSS readers support some semantic features like <strong>, <h1>, or <table>, plus <img> and social media embeddings, and little else. Some add support for a limited set of CSS styles, like [Inoreader](https://inoreader.com/) does, but only for very basic styles.

Publishers, on the other hand, put *everything* into their RSS feed. I have seen forms, complex layouts, external CSS styles, JavaScript. There is no limit. 

Realistically, not everything can be supported by an RSS reader. It still needs to control the rendering to some degree, and it can't allow interactive elements like forms and JavaScript. But I believe far more can be supported than most readers do today.

So this proposal is basically what I consider the maximum you can do in a web-based reader with its own GUI. More may be possible in apps or when using complex (but slow) iframe constructs, but we need to go with the least common denominator.

Not really coincidentally, this is also what my reader Downread supports. But what I am trying here is

- establish a baseline for publishers so they can see what's possible.
- encourage the creators of other RSS readers to allow more HTML and styles
- get feedback. Quite likely I have overlooked issues, or forgotten HTML features that would be useful and should be added. 

[All feedback is welcome](https://github.com/bigwide-net/RFCs/blob/main/RFC-2-HTML-Subset-for-Feed-Content.md).