# Markdown Preview Online - Markdown to HTML Tool

> Free online Markdown previewer: see the rendered result as you type, with GitHub Flavored Markdown tables, task lists, strikethrough and code blocks. Copy the generated HTML in one click; unsafe code is stripped. Runs locally, no upload.

- URL: https://qilingtools.com/en/markdown
- Category: Developer Tools (https://qilingtools.com/en/dev)
- Tags: [Text](https://qilingtools.com/en/tags/text), [Markdown](https://qilingtools.com/en/tags/markdown), [Documents](https://qilingtools.com/en/tags/document), [Developer](https://qilingtools.com/en/tags/dev)
- Last updated: 2026-11-07
- Price: Free, no sign-up
- Privacy: Runs locally in the browser; files are never uploaded

Type or paste Markdown on the left and see it rendered on the right straight away; switch to HTML source to view and copy the converted HTML. It supports GitHub Flavored Markdown (GFM): tables with column alignment, task lists, strikethrough, fenced code blocks and automatic links, and you can mix in common HTML tags such as <kbd>, <sub> and <details>. Use it to check the layout of a README, docs or a blog draft, or to turn Markdown into HTML for a web page. Any scripts hidden in pasted content are removed automatically. Everything runs in your browser, nothing is uploaded.

## How to use

1. Type Markdown on the left, or paste in the contents of a .md file
2. The preview on the right updates as you type
3. When you need HTML, switch to HTML source and click Copy HTML

## Features

- Live preview that refreshes as you type
- GitHub Flavored Markdown: tables with alignment, task lists, strikethrough, fenced code blocks, automatic links
- Mix in common HTML tags such as <kbd>, <sub>, <sup> and <details>
- One-click copy of the generated HTML
- Strips scripts, javascript: links, <style> and other unsafe content without touching normal formatting
- Rendered locally in your browser, nothing uploaded

## FAQ

### Which syntax is supported?

Standard Markdown plus the GitHub Flavored Markdown (GFM) extensions: headings 1 to 6, bold, italic, strikethrough, inline code, ordered and unordered lists, task lists (- [x] and - [ ]), blockquotes, horizontal rules, images, links, automatic links, tables (with :-- and --: for alignment) and fenced code blocks. Footnotes ([^1]), math ($...$), emoji shortcodes (:smile:) and syntax highlighting in code blocks are not supported yet; they show up as plain text.

### Why do line breaks look different from GitHub?

This tool shows a single line break inside a paragraph as a line break, the way GitHub comments and issues do, which feels more natural while writing. When GitHub displays a README or other .md file, though, a single line break counts as a space: you need a blank line for a new paragraph, or two trailing spaces for a line break. So a README preview here may show more line breaks than GitHub does; if you separate paragraphs with blank lines, both look the same.

### How do I use the copied HTML?

You get plain HTML tags such as <h2>, <p> and <table>, with no styling. Pasted into a web page or the HTML mode of a blog editor, it picks up that site's own styles; for email or anywhere that needs a fixed look, add your own CSS. A sample with a table and a code block, for instance, comes out as <table> and <pre><code> tags.

### Is it safe to paste Markdown written by someone else?

Yes. Markdown can contain raw HTML, and a document from elsewhere may hide code that runs on its own, such as <img onerror>, <script> or javascript: links. This tool filters the output before showing it: scripts, event attributes, javascript: links, <style> and <form> are removed, while tables, images, task lists and colored text display as normal. The HTML you copy is the filtered version too.

### Does it slow down on long documents?

We measured it in the browser: a 1,500-line document (19 KB) renders in about 0.08 seconds, and a 15,000-line one (190 KB) with 1,000 tables and 1,000 code blocks in about 0.5 seconds. Up to a few thousand lines you will not notice any delay; very long documents re-render on every keystroke and can feel sluggish, so preview them in sections.

### Is my text kept after I close the page?

No. To avoid leaving your content on the computer, the tool does not save what you type; refreshing or closing the page clears it. For long documents, write in your editor and paste here, or use a tool that saves automatically, such as Online Notepad.

### Do I need to sign up or pay?

No. The site is completely free, needs no account and has no usage limits; your text is processed only in your browser and never uploaded.

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