commonmark-java is a small, fast CommonMark parser with no dependencies. GFM tables, strikethrough, autolinks, task lists, footnotes, front matter and heading anchors come as separate extension JARs. It renders HTML, plain text and Markdown. It’s maintained by Atlassian developers and actively developed. Pick it by default.
flexmark-java started as a fork of commonmark-java and grew into a toolkit: dozens of extensions, emulation of other parsers’ dialects (Pegdown, Kramdown, MultiMarkdown), HTML-to-Markdown conversion, and DOCX and PDF output. Pick it when you need those; note that releases have been rare since 2023.
commonmark-javacommonmark-java parses and renders CommonMark Markdown in Java, with extensions for GFM tables, strikethrough, autolinks and front matter.
flexmark-javaflexmark-java is a CommonMark Markdown parser for Java with dozens of extensions, HTML-to-Markdown conversion and DOCX/PDF output.