Markdown Browser (markdownbrowser.com) is a browser extension and web tool developed by Jan_Wilmake and launched in March 2026. It shows any URL's markdown representation alongside its llms.txt navigation sidebar, providing a unified interface for the "second web" — the markdown and structured-data layer that AI agents consume.
Jan's framing at launch: "The web is bifurcating. For 30 years we had one web — built for human eyes. Now a second web is emerging: markdown, structured data, and llms.txt files that AI agents consume. There's no browser for that second web. Until now."
Markdown Browser solves this by giving humans and agents a consistent way to see both layers of any URL simultaneously.
Jan used Parallel's Extract API as the backend for sites that only serve HTML. This positioned Markdown Browser as a direct showcase for Parallel's Extract API capability and part of his DevRel work.
Markdown Browser was launched as the Agent_Friendly_Web thesis was receiving significant industry validation — with Cloudflare, Mintlify, Vercel, and Bun all adopting markdown-first content delivery in the months prior.