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Markdown Tools

Edit, preview, and convert Markdown in your browser. No uploads.

100% client-side · files never leave your device

Markdown Tools

Why browser-only Markdown tools?

Markdown is a plain-text format used in README files, documentation, blog posts, and notes. Many online Markdown processors send your text to a remote server for rendering or conversion. That is unnecessary — modern browsers can parse and transform Markdown entirely in JavaScript without a round trip to any server. The tools on this page keep your text private and work instantly, even offline after the page has loaded.

Browser-based Markdown tools are also useful for developers who want to check their README output, writers who draft in Markdown and need a word count, and teams who need to audit links or extract a document outline before publishing.

Choosing the right tool

To see how your Markdown looks when rendered, use the Markdown Preview. To convert Markdown to HTML for embedding in a web page, use Markdown to HTML. To convert existing HTML back to Markdown, use HTML to Markdown. To build a Markdown table without memorising the syntax, use the Table Generator. To generate a clickable table of contents for a long document, use the TOC Generator. To audit all URLs in a document before publishing, use the Link Checker.

Frequently Asked Questions

Do my Markdown files get uploaded to a server?
No. Every Markdown tool on this page runs entirely in your browser using JavaScript. Your text and files never leave your device — not even temporarily.
Which Markdown flavour do the tools support?
The tools target CommonMark-compatible Markdown: headings, bold, italic, strikethrough, inline code, fenced code blocks, links, images, ordered and unordered lists, blockquotes, and horizontal rules. GitHub-Flavored Markdown (GFM) tables are supported in the Table Generator.
Can I use these tools to prepare README files?
Yes. The Markdown Preview and TOC Generator are particularly useful for README files. Paste your README, verify the rendered output, then generate a table of contents to paste at the top.
How accurate is the HTML-to-Markdown conversion?
The HTML to Markdown converter handles the most common structural elements: headings (h1–h6), paragraphs, bold, italic, strikethrough, inline code, code blocks, links, images, ordered and unordered lists, blockquotes, and line breaks. Complex tables and deeply nested structures may need manual cleanup.
Does the link checker actually fetch URLs?
Yes. The Markdown Link Checker uses the browser's Fetch API to send a HEAD request to each extracted URL. Requests that return a 2xx or 3xx response are marked as reachable. CORS restrictions may prevent some external URLs from being verified — those are flagged separately.
How does the word count exclude Markdown syntax?
The Markdown Word Count tool strips all formatting — headings markers, bold/italic asterisks, code fences, link syntax, image syntax, and blockquote markers — before counting words. This gives you the true prose word count of your document, not the word count including markup characters.
Can I copy the output to the clipboard?
Yes. Every tool includes a Copy button that writes the output to your clipboard using the Clipboard API, which is supported on all modern browsers including mobile.
Do these tools work offline?
Yes for most tools. All computation runs locally once the page has loaded. The Link Checker requires an internet connection to fetch URLs, but the extraction step works offline.
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