KuConvert

Code & Data

Render Markdown to HTML, safely

Paste Markdown to see the HTML and a rendered preview. Raw HTML is escaped unless you turn it on, and the preview runs in a sandboxed frame with no access to this page.

or paste your own — nothing is uploaded.
HTML

Paste Markdown above and the HTML appears here.

  • Runs in your browser
  • No account required
  • Free to use

How it works

01

Raw HTML is escaped by default

Markdown permits raw HTML, and every renderer has to decide whether to pass it through. Passing it through means a `<script>` in somebody else’s Markdown executes when you preview it. So it is escaped unless you explicitly allow it, and turning it on shows a warning saying what you have just enabled.

02

Dangerous URLs are refused, not encoded

A `javascript:` URL in a link survives HTML escaping completely intact — escaping protects the surrounding markup, not the destination. So link and image URLs are checked, and `javascript:`, `vbscript:` and scripted `data:` URLs are dropped, leaving the label as plain text. Whitespace and control characters are stripped first, because `java&#9;script:` is treated as a scheme by browsers and would slip past a naive check.

03

The preview is sandboxed

It renders in an iframe with no permissions at all, so even with raw HTML enabled nothing in your document can reach this page, read anything or make a request.

04

Code spans are literal

Everything inside backticks is set aside before any formatting runs, so `*not emphasis*` inside a code span stays as asterisks. Backslash escapes are handled the same way — unescaping them at the end would be too late, because the emphasis has already been applied.

What it does

The constructs people actually write

Headings, bold and italic, strikethrough, links, images, ordered and unordered lists, blockquotes, horizontal rules, tables with alignment, inline code and fenced code blocks with a language class.

Live sandboxed preview

Rendered as you type, in a frame that cannot touch anything.

Line-break handling

Optional: treat single newlines as line breaks, which is what chat-style Markdown expects and what CommonMark does not do by default.

Nothing is uploaded

The conversion happens in your browser and the page makes no network requests.

Practical advice

Getting a better result

  • Leave raw HTML off unless you wrote the Markdown. It is the difference between a converter and a way to run someone else’s script.
  • A fenced code block always renders its contents as text, whatever the raw HTML setting says — a code block that renders markup is not a code block.
  • Tables need the dashed delimiter row directly under the header, or the block is treated as a paragraph.
  • Underscores inside a word are not emphasis, so snake_case identifiers survive intact.

Questions

Things people ask

Is it safe to paste Markdown I did not write?

Yes, with the default settings. Raw HTML is escaped, `javascript:` and scripted `data:` URLs are refused, and the preview runs in a sandboxed frame with no permissions. Turning on "allow raw HTML" removes the first of those protections, which is why it warns you.

Which flavour of Markdown is this?

A CommonMark subset with a few widely-used extensions: tables and strikethrough. It covers the constructs people write day to day rather than the whole specification.

Why is my HTML showing as text?

Because raw HTML is escaped by default. Turn on "allow raw HTML" if the Markdown is yours and you meant to include markup.

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Who builds these

Free tools by day. Websites that earn their keep by trade.

KuConvert is built by KUDUY, a web design and development agency. From custom WordPress builds to SEO and e-commerce, everything they do is engineered to bring you more qualified traffic and turn it into revenue.

Web Design

Custom, conversion-focused web design that captivates visitors and turns them into paying customers. Mobile-first, fast, and built to rank.

Web Development

Custom WordPress websites built with clean code, blazing-fast performance (Core Web Vitals optimised), and enterprise-grade security.

E-Commerce

Online stores that convert visitors to customers with seamless shopping experiences.

SEO

Technical SEO, keyword research, on-page optimisation and local SEO strategies that drive qualified organic traffic.

Digital Marketing

Data-driven campaigns that deliver measurable ROI across every channel.

Branding

Memorable brand identities that stand out in any market and build lasting trust.

Website Help

One-on-one expert support for bug fixes, updates and ongoing maintenance — without a long-term retainer.

  • Fixed scope, no surprise invoices

    Most sites ship in four to eight weeks with the scope and the price agreed up front.

  • SEO from day one

    Search is designed into the build — structure, schema and Core Web Vitals — not retrofitted.

  • A team, not a ticket queue

    A project manager, a designer and a developer you can actually reach.

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This tool runs entirely in your browser. Your files are never uploaded.