Which Markdown features does it preview?

Headings, paragraphs, emphasis, links, images, lists, blockquotes, fenced code, GFM tables, task lists, strikethrough and autolinks. Code blocks are displayed as text without syntax highlighting. Footnotes, TeX/LaTeX math and Mermaid diagrams are not rendered by extensions.

Can I convert a Markdown file to HTML?

Yes. Open Markdown file or drop a .md, .markdown, .mdx or .txt file, choose HTML source, then Copy HTML or Download HTML. An .mdx file is read as text, not compiled or executed as JSX. Exports are sanitized HTML fragments rather than a styled, complete website template.

Does my draft stay in this browser?

The draft and a view you explicitly choose can be saved in local storage when the browser permits it. A landing-page preset does not replace your remembered view until you select a view yourself. Clear removes the text; Start over forgets this tool’s stored settings. Private mode, storage quotas or clearing browser data can prevent restoration.

Is the preview or exported HTML identical to GitHub?

It uses marked with GFM parsing, then DOMPurify sanitization. It is not GitHub’s full site renderer, CSS, syntax highlighter or extension set. Preview headings move down one level to fit this page’s outline; HTML exports keep the original heading levels. Sanitization removes scripts and unsafe markup, so it is not a byte-preserving HTML round trip.

Does previewing upload Markdown or load remote images?

The tool does not upload the Markdown text. A rendered preview can request remote images referenced by the document, and clicking a link opens its target normally. HTML source view shows generated text rather than mounting that preview. Saving the HTML does not package referenced images or styles for offline use.

Can I view Markdown with Mermaid, LaTeX or footnotes?

Those extensions are not implemented here. A Mermaid fence remains a code block, TeX remains text and footnote syntax is not evaluated as footnotes. Use a renderer that explicitly supports the needed extension. This tool also has no diff, sharing, collaborative editing or native application workflow.

Can it create an HTML email or a PDF?

It exports an HTML fragment, without email-specific CSS, client compatibility tests or a sending service. For a printable document, use Markdown to PDF, then inspect that tool’s rendering and print limits.

Can I convert HTML back to Markdown?

Use HTML to Markdown. This viewer’s HTML source mode is Markdown-to-HTML output, not an input mode for reversing an HTML document.

Is there an input-size limit?

There is no fixed text or file-size cutoff in this viewer. Parsing, rendering and local-storage capacity still depend on browser memory and device performance; a very large file can take time or fail to be remembered.

Can I embed raw HTML in Markdown?

Supported raw HTML can pass through marked into the preview and exported fragment, but DOMPurify sanitizes it before use. Scripts, event handlers and unsafe targets can be removed. This is not a way to execute JSX, embed a working app or preserve every original HTML byte.

Can I edit a README beside its preview in dark mode?

Yes. The Markdown source and its preview appear side by side on wider screens and stack on smaller ones. The source pane has a dark background, and page appearance follows the site’s theme control. This viewer has no separate theme picker or custom CSS input. The browser can remember your draft, and Open Markdown file reads a local README or other text file.

Markdown Viewer

Paste Markdown or open a .md file to preview headings, tables, fenced code, task lists and strikethrough. Switch to HTML source to inspect the generated fragment, or open Markdown to HTML for that starting view. Copy and download use sanitized HTML with the document’s original heading levels. The renderer does not implement footnotes, math, Mermaid diagrams or executable MDX.

Markdown

Preview

Rendered output appears here as you type.

Drop a .md file, paste, or

Draft kept locallyHTML source exportNothing uploadedRuns in your browser

Common questions

Which Markdown features does it preview?: Headings, paragraphs, emphasis, links, images, lists, blockquotes, fenced code, GFM tables, task lists, strikethrough and autolinks. Code blocks are displayed as text without syntax highlighting. Footnotes, TeX/LaTeX math and Mermaid diagrams are not rendered by extensions.
Can I convert a Markdown file to HTML?: Yes. Open Markdown file or drop a .md, .markdown, .mdx or .txt file, choose HTML source, then Copy HTML or Download HTML. An .mdx file is read as text, not compiled or executed as JSX. Exports are sanitized HTML fragments rather than a styled, complete website template.
Does my draft stay in this browser?: The draft and a view you explicitly choose can be saved in local storage when the browser permits it. A landing-page preset does not replace your remembered view until you select a view yourself. Clear removes the text; Start over forgets this tool’s stored settings. Private mode, storage quotas or clearing browser data can prevent restoration.
Is the preview or exported HTML identical to GitHub?: It uses marked with GFM parsing, then DOMPurify sanitization. It is not GitHub’s full site renderer, CSS, syntax highlighter or extension set. Preview headings move down one level to fit this page’s outline; HTML exports keep the original heading levels. Sanitization removes scripts and unsafe markup, so it is not a byte-preserving HTML round trip.
Does previewing upload Markdown or load remote images?: The tool does not upload the Markdown text. A rendered preview can request remote images referenced by the document, and clicking a link opens its target normally. HTML source view shows generated text rather than mounting that preview. Saving the HTML does not package referenced images or styles for offline use.
Can I view Markdown with Mermaid, LaTeX or footnotes?: Those extensions are not implemented here. A Mermaid fence remains a code block, TeX remains text and footnote syntax is not evaluated as footnotes. Use a renderer that explicitly supports the needed extension. This tool also has no diff, sharing, collaborative editing or native application workflow.
Can it create an HTML email or a PDF?: It exports an HTML fragment, without email-specific CSS, client compatibility tests or a sending service. For a printable document, use Markdown to PDF, then inspect that tool’s rendering and print limits.
Can I convert HTML back to Markdown?: Use HTML to Markdown. This viewer’s HTML source mode is Markdown-to-HTML output, not an input mode for reversing an HTML document.
Is there an input-size limit?: There is no fixed text or file-size cutoff in this viewer. Parsing, rendering and local-storage capacity still depend on browser memory and device performance; a very large file can take time or fail to be remembered.
Can I embed raw HTML in Markdown?: Supported raw HTML can pass through marked into the preview and exported fragment, but DOMPurify sanitizes it before use. Scripts, event handlers and unsafe targets can be removed. This is not a way to execute JSX, embed a working app or preserve every original HTML byte.
Can I edit a README beside its preview in dark mode?: Yes. The Markdown source and its preview appear side by side on wider screens and stack on smaller ones. The source pane has a dark background, and page appearance follows the site’s theme control. This viewer has no separate theme picker or custom CSS input. The browser can remember your draft, and Open Markdown file reads a local README or other text file.

Uses marked’s GFM parsing and DOMPurify HTML sanitization. Preview headings are demoted one level; copied and downloaded fragments keep document heading levels. Footnotes, TeX, Mermaid and executable MDX are not implemented.