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Markdown to HTML

Convert markdown to html in your browser. Escape raw HTML by default, preview in a sandboxed frame, and copy or download HTML. No upload.

Processing mode: Local Browser-local

Sandboxed preview
Waiting for Markdown.

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How to use it

Markdown to HTML Converter — Free, In Your Browser

  1. Paste Markdown into the editor or load a `.md` / `.markdown` / `.txt` file up to 1 MB. Raw HTML escaping is on by default.
  2. Click Convert. The browser-local `marked` parser turns the Markdown into HTML, and the preview iframe renders the result in a sandbox without script permissions.
  3. Copy the generated HTML for embedding, or download a standalone `.html` file. Nothing uploads, and the page does not claim to sanitize untrusted HTML.

Good for

Common use cases

People convert Markdown to HTML when the source is written for humans and the destination only accepts markup. A README draft, changelog entry, product-help article, email snippet, CMS body field, documentation partial, or static-site content block often starts as Markdown because Markdown is fast to write, easy to review in plain text, and friendly to Git diffs. The next system may not understand Markdown at all: an older CMS field expects HTML, a support macro accepts a limited HTML subset, a marketing teammate needs a formatted block for a landing page builder, or a developer wants to paste a pre-rendered article section into a test fixture. The dangerous version of this workflow is pretending conversion equals sanitization. Markdown parsers can pass raw HTML through, links can still point to risky destinations, and pasted snippets from untrusted sources can contain markup you would not want to publish. This page is deliberately framed as a converter, not an HTML sanitizer. It escapes raw HTML by default, renders the preview in a sandboxed iframe, and labels the opt-in raw-HTML mode plainly so you know when the output is carrying markup from the source. That makes the page useful for everyday documentation and CMS work without giving a false security guarantee. The whole workflow runs in your browser: the Markdown is parsed by a vendored `marked` bundle, the generated HTML appears locally, and copy/download happens from the tab. That matters because docs drafts often contain unreleased product names, internal URLs, incident notes, customer examples, or API snippets that should not be pasted into a remote converter just to get `<h2>`, `<ul>`, and `<code>` tags.

Processing mode

Browser-local

Files are processed by your browser. They never reach our servers.

Questions

Markdown to HTML Converter — Free, In Your Browser FAQ

Is this a Markdown to HTML converter or an HTML sanitizer?

It is a Markdown to HTML converter. The page can escape raw HTML inside the Markdown before parsing, and the preview iframe is sandboxed, but that is not the same thing as sanitizing arbitrary untrusted HTML for publication. If your source comes from users or from a place you do not trust, run the final HTML through a real sanitizer in the destination stack, such as DOMPurify on the frontend or an allowlist sanitizer on the server. This page is for converting trusted Markdown drafts into HTML, not for proving that the output is safe to publish anywhere.

What happens to raw HTML inside the Markdown?

Raw HTML is escaped by default, so a pasted `<script>`, `<iframe>`, or example `<div>` appears as text in the generated HTML rather than becoming active markup. If you turn on "Allow raw HTML", the parser passes raw HTML through into the output because that is what Markdown parsers traditionally allow. The UI labels that mode as trusted-source only. The preview still renders in a sandboxed iframe without script permissions, but copied output can carry whatever raw HTML you allowed through.

Does the converter match GitHub Markdown exactly?

No. The parser runs with GitHub-flavoured Markdown features enabled, so tables, fenced code blocks, autolinks, and task-list syntax work, but GitHub's renderer also applies its own HTML transforms, slug generation, syntax-highlighting pipeline, link policies, and CSS. Treat this page as a fast structural converter: it tells you which HTML tags the Markdown expands into. It does not promise pixel-perfect GitHub display.

Why does the page use an iframe for preview instead of writing HTML into the page?

The generated HTML is conversion output. Writing it directly into the tool UI would mix user-provided markup with the application DOM and make it easier for a bad snippet to interfere with the page. The preview uses a sandboxed iframe so the converted document is isolated and scripts are not allowed to run. Copy and download still use the textarea output, which keeps the generated HTML inspectable before you paste it anywhere else.

Can I use this for email HTML?

You can convert Markdown into basic HTML and then paste it into an email-building workflow, but this page does not test email-client compatibility. Email HTML has its own constraints: inline styles, table layouts, blocked media, client-specific CSS support, and link rewriting. Use this page for the Markdown-to-HTML step, then test the result in the email platform or preview service that will actually send it.

Are Markdown links and images checked or rewritten?

No. Links and image references are converted into `<a>` and `<img>` tags according to the parser's Markdown rules. The page does not fetch URLs, check whether links are reachable, rewrite relative paths, proxy images, or validate whether a URL is safe for your destination. That is intentional: fetching remote resources would break the local-processing model and turn a converter into a crawler.

What size Markdown files can I convert?

The transform is capped at 1 MB of text per run. Markdown parsing happens in memory, and the generated HTML can be larger than the source when there are many links, tables, or code blocks. For bigger documentation sites, use a build tool such as Markdown-it, unified/remark/rehype, or your static-site generator in a local project where the conversion can stream through files and apply project-specific plugins.

Will this tool stay free?

The basic workflow is designed to stay free. Paid upgrades later will focus on bigger limits, batch work, OCR, saved presets, and ad-free use.