Portable rich text
Headings, emphasis, lists, links, and images are copied from the rendered preview instead of raw Markdown.
Substack formatting
Paste Markdown into Substack without rebuilding the article
Turn one Markdown draft into portable rich text, including headings, lists, links, images, math, and Mermaid diagrams.
newsletter.md
# A technical newsletter A clear **opening idea**. - Evidence - Implication - Next step Math: $E=mc^2$
A format-first workflow for newsletters
Keep writing in Markdown. The converter prepares a Substack-specific preview and a rich clipboard payload.
Math, diagrams, and tables
MathJax, Mermaid, and Markdown tables are converted into portable images before the rich copy is created.
Chinese or English
Keep the original Chinese article or generate a single English version through your own OpenRouter configuration.
From draft to Substack in three steps
Add your Markdown
Paste the draft and attach any unresolved local images referenced by Obsidian.
Review the preview
Confirm headings, links, images, formulas, and diagrams before copying.
Copy rich content
Use “Copy rich content,” paste into Substack, and complete the final editorial check.
Know the boundaries
- Remote image hosts that block browser access may prevent the image binary from entering the clipboard.
- Substack does not provide a native table block, so Markdown tables are copied as images.
- A publication can choose custom title and body fonts, while the converter previews Substack's default article theme.
- The tool formats content; it does not sign in, schedule, or publish on your behalf.
Frequently asked questions
Does Substack support raw Markdown paste?
Markdown structures may be interpreted inconsistently. This tool copies the rendered result as rich content instead of relying on Substack to parse the source.
Can formulas and Mermaid diagrams survive paste?
They are rendered first and converted into portable visual assets for the clipboard workflow.
Is my draft uploaded?
No. Conversion runs in the browser. Your article and local images are not sent to this project’s server.
Prepare your next Substack draft
Keep Markdown as your source of truth and copy a publish-ready version.
Open the Substack converter