What is this Markdown to Substack converter?
A free, browser-based tool that turns Markdown into clean HTML you can paste straight into the Substack editor. Substack does not interpret raw Markdown, but it does keep formatting when you paste rich HTML — so this tool converts headings, bold, italic, lists, blockquotes, links, images, and horizontal rules into that HTML, shows a live preview, and flags elements Substack tends to break (tables, footnotes, deep headings, nested lists, raw HTML, and code blocks). Everything runs locally in your browser, so your draft is never uploaded.
How to use it
- Paste your Markdown into the box on the left.
- Review the converted HTML and the live preview on the right.
- Check the warnings for any unsupported elements and fix them by hand if needed.
- Copy the HTML and paste it into the Substack composer.
Common use cases
- Drafting newsletters in Markdown (in your editor or notes app) and publishing them on Substack.
- Repurposing a Markdown blog post or README into a Substack issue.
- Catching formatting that Substack will break before you hit publish.