A minimal, elegant side-by-side markdown editor with live preview. No sign-up required.

Live app: Set NEXT_PUBLIC_SITE_URL to your deployment URL (e.g. https://markos.app) and deploy. The app runs in the browser with no backend required.

• Live preview — Write markdown on the left, see the rendered result on the right in real time.
• No account — Use the editor immediately without signing up or logging in.
• In-browser — Runs entirely in the browser; your content stays local unless you choose otherwise.
• Theme — Light/dark mode with system preference support.

• Next.js (App Router), React, Tailwind CSS, react-markdown.

pnpm install
pnpm dev

Open http://localhost:3000.

• Set NEXT_PUBLIC_SITE_URL in production so metadata, sitemap, and Open Graph use the correct base URL.
• For best social link previews (Twitter, LinkedIn, etc.), add a 1200×630 image at public/og.png. The app uses public/og.svg as a fallback.