About the Markdown Editor
The Markdown Editor is a split-pane writing surface: type Markdown on the left and watch the rendered HTML preview update keystroke-by-keystroke on the right. Supports the full CommonMark spec plus the GitHub Flavored Markdown (GFM) extensions you actually use — tables, fenced code blocks with syntax-aware backticks, task lists, strikethrough, and autolinking. A toolbar covers H1–H3, bold, italic, links, images, code blocks, and tables; keyboard shortcuts (Ctrl+B / Ctrl+I / Ctrl+K) match every other editor.
It is built for technical writers drafting README files, developers writing docs without leaving the browser, bloggers using a CMS that accepts Markdown but lacks a preview, content marketers writing for Ghost / Substack / Hashnode, and anyone wanting a quick scratchpad for note-taking that produces clean output ready to paste anywhere.
All rendering happens locally in JavaScript. Whatever you type — technical drafts, internal documentation, journal entries, unpublished posts — never leaves your device. The page makes no network call after first load. Reload the tab and your text is gone (use export to .md or HTML before closing if you want to keep it); cookies and local storage are not used.
The parser follows CommonMark plus GFM, which means a handful of older “Markdown extras” (footnotes in some flavors, citation syntax, math-mode $\LaTeX$) are not supported. The HTML output is unsanitized inside code blocks; if you plan to paste user-supplied Markdown into a public-facing page, run it through a sanitizer (DOMPurify) before serving. For Markdown that targets a specific renderer (Pandoc, MkDocs, Hugo), test in that renderer too.
Paste HTML to convert to Markdown, or export your Markdown as clean HTML.
Markdown Syntax Quick Reference
Markdown uses simple text formatting characters that are converted to rich HTML. Headings use hash marks (#), emphasis uses asterisks (* or **), code uses backticks, and links use square brackets followed by parentheses. This editor supports all standard Markdown plus GitHub Flavored Markdown extensions for subscribers.
What Is Markdown and Why Use It?
Markdown is a lightweight markup language created by John Gruber in 2004. It lets you write formatted text using plain characters that are easy to read even without rendering. Markdown is the standard for GitHub, Reddit, Stack Overflow, Discord, Notion, Jekyll, Hugo, and many documentation platforms. Learning Markdown makes you more productive across dozens of tools.
Common Markdown Formatting
Headings are created with hash marks (# for H1, ## for H2, ### for H3). Bold text uses double asterisks (**bold**), italic uses single asterisks (*italic*), and inline code uses backticks. Links follow the pattern [text](url), and images are similar with an exclamation mark prefix. Code blocks use triple backticks with an optional language identifier for syntax highlighting.
Markdown Tables
Tables use pipe characters (|) to separate columns and hyphens (-) to create the header separator. Alignment is controlled with colons: left-aligned (default), center-aligned (:---:), or right-aligned (---:). This editor inserts a table template when you click the table button in the toolbar.
Markdown Flavors: CommonMark, GFM, and Beyond
The original Markdown specification by John Gruber left many edge cases ambiguous, leading different platforms to interpret the same syntax differently. CommonMark was created in 2014 to standardize the rules, providing a precise, unambiguous specification that most modern parsers now follow. GitHub Flavored Markdown (GFM) extends CommonMark with additional features: tables, task lists (- [x] syntax), strikethrough (~~text~~), and fenced code blocks with syntax highlighting. Beyond GFM, other platforms implement their own variants: Slack uses a simplified subset without headings, Reddit has its own table and spoiler syntax, Notion renders most GFM but handles some elements visually rather than as raw Markdown, and Obsidian adds wikilinks and callouts not found in any standard spec. This means content that renders perfectly in one tool may look different in another, so it is always worth previewing Markdown in the target environment before publishing.
Converting Markdown to HTML, PDF, and Other Formats
Markdown’s real power is as a source format that can be converted into virtually any output. Pandoc is the gold-standard command-line converter: it transforms Markdown into Word documents (.docx), PDF (via LaTeX), HTML, EPUB, PowerPoint, and dozens of other formats with a single command, making it indispensable for technical writers and academics. Static site generators like Hugo, Jekyll, and Eleventy render entire websites from Markdown files, combining content with templates to produce full HTML pages at build time. For browser-side rendering, JavaScript libraries such as Marked.js and Showdown.js parse Markdown and output HTML in real time — the same approach this editor uses for its live preview. If you work in VS Code, the built-in Markdown preview (Ctrl+Shift+V) shows how your document will look before export, and extensions like Markdown PDF let you export directly to PDF without leaving the editor. Understanding your output target before you start writing helps you choose the right Markdown flavor and avoid formatting surprises downstream.
Looking for related tools? Try our Word & Character Counter to analyze your document’s length and reading time, or explore all Writing & Content tools.
