Markdown editor with live preview
Write on the left and see your Markdown rendered on the right, instantly. Use GitHub-flavored syntax, copy either the Markdown or the generated HTML, and work entirely in your browser with nothing uploaded.
How to use Markdown Editor
- 1
Start writing
Type Markdown in the left panel — a sample is there to get you started.
- 2
Watch the live preview
The right panel renders your Markdown instantly as you type.
- 3
Use GitHub-flavored syntax
Headings, lists, links, tables and code blocks all render as expected.
- 4
Copy what you need
Copy the raw Markdown or the generated HTML with one click.
Write and preview, side by side
The best way to write Markdown is to see it taking shape as you go, and that is exactly what a split-screen editor gives you. You type in the panel on the left and the panel on the right shows your text rendered the way it will actually appear, updating with every keystroke. There is no separate 'preview' button to click and no mental translation required between the symbols you type and the formatting they produce. Add a heading and it appears, styled, the instant you type the hash; start a list and watch it indent; paste a link and see it become clickable. This immediate feedback makes writing Markdown faster and far more pleasant, especially for longer documents where small formatting mistakes are easy to miss in raw text. Instead of writing, switching context to check, and switching back, you stay in a single flow with the finished look always visible beside your words.
GitHub-flavored Markdown, fully rendered
The editor supports GitHub-flavored Markdown, the dialect most people actually write, so the preview reflects the full range of formatting you use rather than a stripped-down subset. Headings, bold and italic, ordered and unordered lists, links, images, blockquotes, horizontal rules, inline code and fenced code blocks all render the way you expect, and tables built from pipes and dashes are drawn with proper borders. Line breaks behave sensibly, so the text you write reads the same in the preview as it does in your head. Because the rendering matches the conventions used in README files, documentation and notes apps, what you compose here will look the same when you take it elsewhere. That consistency is the whole point of a preview: it is only useful if you can trust that the rendered result you see is the result you will get when the Markdown is published or pasted into another GFM-aware system.
Copy the Markdown or the HTML
When your document is ready, you need to get it out of the editor, and how you want it depends on where it is going. Sometimes you want the Markdown itself — to commit a README, paste into an issue, save a note, or hand to another Markdown-aware system. Other times you need the rendered HTML — to drop into a web page, an email template or a CMS that expects markup. In1 lets you copy either with a single click: grab the raw Markdown from the editor side, or copy the generated HTML from the preview side. You are never locked into one format or forced to run the text through a second tool to get the other. This dual output makes the editor useful both as a comfortable place to write Markdown and as a quick way to turn that Markdown into publishable HTML, covering the two things people most often need to do with it.
Private by design — nothing leaves your browser
Whatever you are writing — documentation, a draft post, private notes, a README for an unreleased project — it stays on your own device. In1's Markdown editor runs entirely in your browser using plain JavaScript, so neither your Markdown nor the rendered HTML is ever uploaded to a server. There is no account to create, no document stored in the cloud and nothing left behind when you close the tab. The preview and both copy actions work with no network request, which means the editor is instant and fully functional offline — you can write on a plane or behind a firewall and it behaves exactly the same. This local-only design is what makes it safe to draft sensitive or unpublished content here, and it is also what keeps the experience fast and reliable: there is no syncing, no loading and no failure mode tied to your connection. You just write, and the preview keeps up.
Who uses an online Markdown editor?
Plenty of people write Markdown but do not always have their preferred editor open. Developers draft README files, documentation and issue descriptions and want to see them rendered before committing or posting. Technical writers compose docs in Markdown for its speed and clarity. Bloggers and content creators write posts in Markdown and need to preview them and grab the HTML for their platform. Students and researchers take structured notes in Markdown and like seeing them formatted. Open-source maintainers polish project pages. Anyone jotting something down who wants clean formatting without wrestling with a word processor reaches for Markdown, and a browser-based editor with a live preview means they can do it anywhere, on any device, without installing anything. Being able to copy either the Markdown or the HTML at the end makes it a practical one-stop tool: a comfortable place to write and an instant way to publish what you wrote. It is equally handy for quick one-off tasks — formatting a comment, drafting release notes, or cleaning up a snippet someone sent you — where opening a full application would be overkill. Because the preview is always visible beside the text, even people who do not write Markdown often can experiment, see what each symbol does, and learn the syntax by watching it render in real time rather than memorizing rules.
Higher limits, batch processing and an API are on the way. Want early access?