Overview
Markdown is the closest thing the web has to a universal writing format: plain text with a few unobtrusive marks — # for headings, * for emphasis, - for lists — that any tool can turn into a proper document. READMEs, chat messages, documentation, notes apps and static sites all speak it, which makes a live preview the fastest way to learn it and the most pleasant way to write it.
This previewer renders the common Markdown subset as you type: headings, bold and italic, lists, links, images, inline code and fenced code blocks, blockquotes, tables and horizontal rules. When the document looks right, copy the generated HTML or download the source file.
Why does Markdown exist?
Because writing HTML by hand is slow and writing in a word processor hides the structure. Markdown's bet — made by John Gruber in 2004 — is that the marks should be readable as plain text even before rendering: *this* obviously means emphasis, # obviously means a heading. The source stays legible in any editor, in any decade, with no special software.
The trade-off is that Markdown is a family of dialects, not one standard. Basic syntax (headings, lists, emphasis, links) works everywhere; tables, footnotes and task lists vary. This previewer implements the widely-shared core plus GitHub-style tables and fenced code blocks, and says plainly what it supports so you are never surprised.
Features
- Live side-by-side preview that re-renders with every keystroke.
- Common-subset support: headings, emphasis, lists, links, images, code, quotes, tables, rules.
- Fenced code blocks with HTML-escaped contents that cannot break the page.
- GitHub-style tables with header detection and alignment rows.
- Copy HTML for pasting into CMSs and emails; download .md to keep the source.
- Safe by construction: raw HTML in the source is escaped, never executed.
Benefits
- Learn Markdown by doing. Type a mark, see the result instantly.
- Draft anywhere. READMEs, docs and posts without opening a heavy editor.
- Portable source. The .md file works in GitHub, notes apps and static generators.
- Private: your writing never leaves the browser.
Who can use it
Developers writing READMEs and documentation, writers drafting posts for static sites, students taking notes they will publish later, support staff writing help articles, and anyone curious what the fuss about Markdown is. If you have ever fought a word processor over heading styles, this is the calmer alternative.
How to use
- Type or paste Markdown in the left pane (a sample document is preloaded).
- Watch the formatted preview update live on the right.
- Use Copy HTML to take the rendered output into a CMS or email.
- Use Download .md to save your source file.
- Press Clear to start a fresh document.
Frequently asked questions
Will my Markdown render the same on GitHub?
For the common subset — headings, emphasis, lists, links, code, quotes — yes, essentially identically. Tables match GitHub's style too. Exotic extensions (footnotes, task lists, math) are not supported here, so check those in their own previewers.
Can I include raw HTML in my Markdown?
You can type it, but it will be escaped and shown as text, not executed. That is deliberate: executing arbitrary HTML from a previewer would be a security hole (cross-site scripting). For trusted publishing pipelines, use a full Markdown processor instead.
Why do my line breaks disappear?
Because standard Markdown treats a single line break as a space — paragraphs are separated by blank lines. End a line with two spaces for a hard break, or leave a blank line for a new paragraph. The previewer follows the standard rule.
How do I make a table?
Write a header row in pipes, then a separator row of dashes (| --- | --- |), then your data rows. Column alignment with colons (| :--- | for left, | ---: | for right) is accepted in the separator row.
Is my document uploaded anywhere?
No. Rendering happens entirely in your browser; the text lives in the page until you download or copy it.
Conclusion
Markdown's promise is that the source is the document — readable now, renderable forever. Write it plain, preview it live, and keep the .md file: unlike proprietary formats, it will still open in thirty years.