Everything you need to know about DownStack.
DownStack is a tool that converts markdown to Substack-ready rich text. The key feature is that tables are automatically converted to clean, hosted images that display perfectly in Substack posts and email newsletters.
When you click "Copy for Substack," DownStack renders each table in your markdown as a styled image, uploads it, and puts the hosted image in the rich text. Substack then displays that image in the post and in subscriber emails.
No. The editor works without an account. Creating an account is optional.
Table images are stored on Cloudflare and served from there. They are not kept in your browser as temporary data URLs.
Yes. Your markdown content is processed entirely in your browser. We do not store, read, or analyze your content. The only data sent to our servers is the rendered table images for hosting. Authentication is handled by Supabase with industry-standard encryption.
DownStack supports full GitHub Flavored Markdown (GFM): headings, bold, italic, links, lists, blockquotes, code blocks, tables, images, horizontal rules, and Mermaid diagrams. We're continually adding support for more features.
While DownStack is optimized for Substack, the rich text output works with any platform that supports pasting HTML content — including Ghost, WordPress, Medium, and email clients.
We'd love to hear from you! Head to our contact page and send us a message. We read every submission and respond within 24 hours.
Still have questions? Contact us and we'll get back to you within 24 hours.