Markdown Preview
Write GitHub-flavored Markdown and see the rendered result live.
Rendering happens in your browser. Internal documentation, drafts and anything else you paste are never uploaded.
Markdown gets written in places that do not show you what it will look like: a commit message editor, a ticket comment box, a README typed over SSH. The gap between "I think that table is right" and "that table is right" is exactly one preview, and pasting internal docs into a random website to get that preview is how confidential text ends up in other people's logs.
More about Markdown Preview
This preview runs entirely in your page. Type or paste GitHub-flavored Markdown on the left and the rendered result appears on the right as you type — tables with alignment, task lists as checkboxes, strikethrough, fenced code blocks with their language label, blockquotes, reference links and autolinks.
It is built to be safe against hostile documents, not just convenient for friendly ones. Raw HTML in the source is shown as text, never parsed, which is where markdown-based script injection lives. Link destinations are checked after decoding the tricks used to disguise them, so a javascript: URL cannot hide behind entity encoding; data: URLs are refused for links and images alike.
The renderer builds the page from the document's structure directly — at no point does an HTML string exist to be injected. That is a stronger property than sanitizing output afterwards, and it is why pasting a README from an untrusted repository here is safe.
Fidelity target: what GitHub shows for ordinary documents. Code blocks are not syntax-highlighted in this version, and exotic HTML-based layouts will show as their source text, by design.
- Live preview with GitHub-flavored extras: tables, task lists, strikethrough
- Raw HTML displayed as text — markdown XSS has nowhere to run
- Link and image URLs allowlisted after entity-decoding tricks are undone
- Fenced code blocks with their language label
- Reference links, autolinks, setext headings, nested quotes and lists
- Large documents rendered off the main thread
- Copy the Markdown source with one click
How to use it
- 1Type or paste Markdown into the left pane, or load the example.
- 2Read the rendered result on the right as you type.
- 3For very large documents, press Run when asked.
- 4Copy the source with the button below when you are done.
Questions
Why does my inline HTML show as code instead of rendering?
By design: raw HTML is where every markdown injection attack lives, so it is displayed as text rather than parsed. A preview that renders your <div> also renders an attacker's <script>.
Will it look exactly like GitHub?
For ordinary documents — headings, lists, tables, code, quotes — yes, this is a GitHub-flavored preview. Pixel-identical rendering is not the goal: GitHub applies its own CSS, and HTML-based tricks are deliberately shown as text.
Why is there no syntax highlighting in code blocks?
Highlighting grammars for every language would multiply the download for a feature most previews do not need. Code blocks keep their language label, so the information is preserved; highlighting may come later.
What happened to the link I wrote with a javascript: URL?
Its text is still there, but the link itself was removed: destinations are checked after undoing entity and control-character disguises, and only http, https, mailto and relative URLs survive. data: URLs are blocked too.
Can I export the result as HTML?
No — deliberately: this tool never produces an HTML string anywhere, which is a large part of why it is safe. Copy the Markdown source instead; every serious platform renders it natively.