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iToolVersev4.2

Markdown Viewer & Editor

Live preview, CodeMirror editor, GitHub Flavored Markdown, syntax-highlighted code blocks, HTML export

Write GitHub Flavored Markdown on the left, see it rendered on the right in real time. The editor is powered by CodeMirror with markdown syntax highlighting; code blocks in the preview use CodeMirror too, so you get accurate highlighting for JavaScript, TypeScript, HTML, CSS, JSON, YAML, XML, and Markdown. Tables, task lists, strikethrough, and blockquotes are all supported. Copy or download the result as Markdown or self-contained HTML.

Quick Templates

Markdown Input

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Worked examples

Six common markdown patterns. Click Copy on any card to put its source into your clipboard, then paste it into the editor above to see it rendered live.

GitHub README

Docs

Standard layout for an open-source project README — title, description, install, usage, license.

HeadingsFenced codeListsBash + JS highlighting

API endpoint documentation

Docs

A single API endpoint with parameters table, JSON request/response examples, and error codes.

Tables with alignmentJSON syntax highlightingInline code

Meeting notes with task list

Notes

Day-of meeting capture with attendees, decisions, and follow-up checkboxes.

Task listsBlockquoteNumbered lists

Tutorial with multiple code blocks

Tutorial

Step-by-step writeup mixing prose, terminal commands, and TypeScript examples.

Mixed code blocks (bash + TS)AutolinksInline code

Changelog entry

Release

A single release entry following the Keep a Changelog format.

Versioned headingsGrouped lists

GFM extras showcase

Demo

Strikethrough, autolinks, footnotes, task lists — every GFM extra on a single page.

StrikethroughAutolinksFootnotesAligned tables

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Markdown reference

Quick syntax reference for everything this viewer renders, plus the differences between CommonMark and GitHub Flavored Markdown that catch most people the first time.

Syntax cheat sheet

Inline
  • # Heading 1
  • ## Heading 2
  • **bold** · *italic*
  • ~~strikethrough~~
  • `inline code`
  • [link text](https://url)
  • ![alt text](image.png)
Block
  • - bullet item
  • 1. ordered item
  • - [x] completed task
  • > blockquote
  • | col 1 | col 2 | (table)
  • ```javascript (fenced code)
  • --- (horizontal rule)

CommonMark vs GitHub Flavored Markdown

CommonMark is the official Markdown spec. GitHub Flavored Markdown (GFM) extends it with a few extra features used everywhere on GitHub, GitLab, and most modern Markdown processors. This viewer renders GFM.

FeatureCommonMarkGFM
Headings, bold, italic, links, lists✓✓
Fenced code blocks✓✓
Tables (| col |)—✓
Task lists (- [x])—✓
Strikethrough (~~text~~)—✓
Autolinks (bare URLs)—✓
Footnotes [^1]—✓

Code block syntax highlighting

Fenced code blocks accept a language hint after the opening triple-backticks. This viewer uses CodeMirror to highlight the following languages natively:

  • JavaScript / TypeScript / JSX / TSX — js, ts, jsx, tsx
  • HTML — html
  • CSS / SCSS / SASS / LESS — css, scss, sass, less
  • JSON / JSONC — json, jsonc
  • YAML — yaml, yml
  • XML / SVG — xml, svg
  • Markdown — md, markdown, mdx

Any other language hint (e.g. python, go, bash) renders as a clean monospaced block without syntax colouring — readable, just not coloured. Adding more languages is a one-line change in the code block component.

Common uses

  • READMEs for GitHub / GitLab / Bitbucket repositories — the rendered output matches platform behaviour because both use GFM.
  • Technical documentation — API reference, runbooks, internal guides.
  • Blog drafts — write in Markdown, export the HTML, paste into your CMS.
  • Meeting notes & reports — task lists make follow-ups easy to track.
  • Static-site content — Hugo, Jekyll, Astro, Next.js all consume Markdown directly.
  • Quick HTML conversion — sometimes you just need styled HTML to email or paste into a doc.

Exporting

  • Copy Markdown — raw source, useful for moving content between editors.
  • Copy HTML — self-contained HTML with inline styles. Paste into an email or doc.
  • Download HTML — same self-contained HTML saved as a .html file.
  • Download MD — the original Markdown source saved as document.md.

Everything runs in your browser — nothing is uploaded.

Frequently Asked Questions

GitHub Flavored Markdown, CodeMirror syntax highlighting, exports, and the React-Markdown rendering pipeline.