Meet ReverseMarkdown

ReverseMarkdown is a HTML to Markdown converter library in C#. v6 uses AngleSharp's HTML5-compliant parser and a Markdown DOM pipeline for reliable, performant conversion.

📖 Full documentation: mysticmind.github.io/reversemarkdown-net

Using v5.x? See the v5.x documentation.

If you have used and benefitted from this library. Please feel free to sponsor me!

Install

dotnet add package ReverseMarkdown

Quick start

var converter = new ReverseMarkdown.Converter();

string html = "This a sample <strong>paragraph</strong> from <a href=\"http://test.com\">my site</a>";

string result = converter.Convert(html);
// This a sample **paragraph** from [my site](http://test.com)

With configuration and a flavor:

var config = new ReverseMarkdown.Config
{
    Flavor = MarkdownFlavor.GitHub,
    Formatting = { RemoveComments = true },
    Links = { SmartHref = true },
};

var converter = new ReverseMarkdown.Converter(config);

Features

• Seven output flavors - Default, GitHub, CommonMark, Slack, Telegram, MultiMarkdown, and Pandoc, selected via the Flavor enum.
• Spec-compliant round-trips - CommonMark and GitHub Flavored Markdown round-trip at 100% against canonical cmark-gfm; MultiMarkdown and Pandoc verified against canonical pandoc.
• Extensible - custom readers (IMdReader + [MarkdownReader]), tag aliases, and a Parse/Render Markdown DOM for direct transformation.
• Tables, links, and images - nested tables and captions, smart href handling, URI-scheme whitelisting, and base64 image handling (include / skip / save to disk).
• Broad framework support - targets netstandard2.0, net8.0, net9.0, and net10.0 (runs on .NET Framework 4.6.1+, .NET Core 2.0+, Mono, and Unity).
• Trimming and Native AOT ready - the default conversion path uses no reflection; add custom readers with RegisterReader under trimming/AOT. See Supported Frameworks.

Performance

v6 replaces the v5 HtmlAgilityPack engine with an AngleSharp HTML5 parser feeding a Markdown DOM and per-flavor writers. It is roughly 2–2.6× faster than v5 and allocates about 2.7× less memory.

Measured with BenchmarkDotNet on .NET 9.0 (Apple M1), comparing published ReverseMarkdown 5.5.0 vs 6.0.0 on the same inputs (lower is better):

Fixture	Mean time v5 → v6	Allocated v5 → v6
1000 paragraphs	13.7 → 5.2 ms (2.6× faster)	21 → 7 MB (2.8× less)
10k paragraphs	119.1 → 63.1 ms (1.9× faster)	183 → 67 MB (2.7× less)
huge.html	540.6 → 244.3 ms (2.2× faster)	779 → 288 MB (2.7× less)

See the Performance guide for details and how to reproduce the benchmark.

Documentation

The full guide lives at mysticmind.github.io/reversemarkdown-net:

• Getting Started
• Performance
• Flavors
• Configuration reference
• Extending (custom readers, recipes)
• Migrating from v5

Acknowledgements

This library's initial implementation ideas from the Ruby based Html to Markdown converter xijo/reverse_markdown.

Copyright

Copyright © Babu Annamalai

License

ReverseMarkdown is licensed under the MIT License.