Parsoid/Users

Parsoid's output is now used in a lot of places directly or indirectly. Parsoid will serve all read views relatively soon. This page is more of historical interest and isn't actively maintained.

Wikimedia

VisualEditor – Parsoid provides HTML and converts modified HTML back to wikitext on page save
VisualEditor's 2017 wikitext editor – for page previews, upon inserting citoid citations, etc.
Flow (Structured Discussions) – Parsoid provides a wikitext editor for HTML discussions
PDF rendering – Parsoid provides the structured HTML input for conversions to LaTeX, PDF (both via PDF and phantomjs) and other offline formats
Mobile Content Service is working on using structured Parsoid HTML+RDFa as the input for both mobile web & apps, including the Android app.
The Content translation project is aiming to translate Parsoid HTML with the help of machine translation and data sources like Wikidata. Parsoid is used to get semantic HTML + RDFa from an article in another language, and to convert the translated HTML+RDFa back to wikitext for a new article.
Linter extension – This recently developed extension exposes Parsoid-identified wikitext markup errors to editors for fixup. As of March 2017, this extension is in the process of being rolled out to Wikimedia wikis.
REST API

Gadgets

Google translate based new page tool for Czech -> Slovak, Google translation; the Parsoid HTML is translated and then converted back to wikitext.
Jackmcbarn's editProtectedHelper – specialized template editor; Parsoid HTML is edited and converted back to wikitext

Bots

Third party tools

Kiwix – Offline Wikipedia reader for smartphones, desktops etc; Parsoid provides structured HTML
Google knowledge graph team – extracts semantic information from Wikipedia pages; Parsoid provides structured HTML.
Nell's Wikipedia – Offline/online reader for literacy learning. See "Learning Literacy with Wikipedia" presentation at Wikimania 2014.