Markdown, HTML and BBCode Converter
Convert between Markdown, HTML and BBCode through a strict whitelist. Dangerous tags and javascript: URLs are removed, and every format that gets lost is listed. Includes a safe preview.
- Runs in your browser (no upload)
Links and images are kept only with URLs that start with http:// or https://. Unsupported formatting is removed and listed below.
Processing…
Supported formatting (whitelist)
Formatting not in this table (colors, font sizes, tables, embeds…) is removed. “—” means the format has no such syntax.
| Format | Markdown | HTML | BBCode |
|---|---|---|---|
| Bold | **text** | <strong> <b> | [b] |
| Italic | *text* _text_ | <em> <i> | [i] |
| Underline | — | <u> <ins> | [u] |
| Strike-through | ~~text~~ | <s> <del> <strike> | [s] [strike] |
| Link | [text](https://…) | <a href="https://…"> | [url] [url=https://…] |
| Image |  | <img src="https://…" alt="…"> | [img]https://…[/img] |
| Bulleted list | - item | <ul><li> | [list][*] |
| Numbered list | 1. item | <ol><li> | [list=1][*] |
| Quote | > text | <blockquote> | [quote] [quote=name] |
| Code block | ```lang | <pre><code> | [code] [code=lang] |
| Inline code | `code` | <code> | [icode] |
| Heading | # … ###### | <h1> … <h6> | [h1]…[h6] [heading=1] |
| Horizontal rule | --- | <hr> | [hr] |
| Line break / paragraph | ␣␣↵ | <br> <p> | ↵ |
How to use
- Choose the direction, for example Markdown → HTML.
- Type or paste your text. The result and the preview appear immediately.
- Check “What the conversion loses or changes”, then copy or save the result.
FAQ
Which formatting is supported?
Bold, italic, underline, strike-through, links, images, bulleted and numbered lists, quotes, code, headings, horizontal rules and line breaks. Colors, font sizes, tables, embeds and similar formatting are removed and listed.
Is dangerous code removed?
Yes. Elements such as script and iframe, event attributes such as onerror and URLs other than http/https (javascript:, data:…) are removed. HTML output and the preview are also passed through DOMPurify with the same whitelist.
Does BBCode differ between forums?
Yes. BBCode has no single standard, so only tags common to most forums are used. Formats without a common tag, such as headings and rules, are replaced with bold text or plain text and reported.
Notes & limitations
- What you enter is processed only on this page and is not sent to YUCTS servers.
- BBCode differs between forums. Tags outside this tool’s whitelist (color, size, spoiler…) are removed.
- Markdown is read as GitHub Flavored Markdown by marked. Tables, task lists and footnotes are not kept.
- The preview does not load external images. If you paste the HTML into another site, that site’s own rules also apply.
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