UBB and HTML Converter

Features

• Inline tags: bold, italic, underline, strikethrough, colour, size, font and alignment
• Both link forms ([url]address[/url] and [url=address]text[/url]), plus email and images
• Quotes (including [quote=name] attribution), code blocks, and ordered and unordered lists
• Nesting closed in the correct order — what a find-and-replace converter cannot do
• Unclosed tags are closed at the end, and stray closing tags are treated as plain text
• Tag names are case-insensitive: [B] is the same as [b]
• Sizes map through the Discuz 1–7 scale rather than becoming font-size: 7px
• Square brackets inside a [code] block are left alone — that is the code itself
• Unrecognised tags survive untouched, so the user layout does not vanish
• javascript: links degrade to plain text instead of producing a clickable <a>
• The HTML → UBB direction covers paragraphs, lists, quotes, code blocks and inline formatting
• Everything runs locally in the browser; your content is never uploaded

How to use

1. Paste the forum code or the HTML
2. The direction usually needs no choosing — a leading < is read as HTML
3. Turn off the line-break option if you need to
4. Copy the result

FAQ

Why does nesting need a stack?

Because which `[i]` a given `[/i]` closes is only knowable from the full tag sequence. A converter that runs find-and-replace step by step turns `[b]bold[i]italic[/i]still bold[/b]` into crossing tags (`<strong>bold<em>italic</strong>still bold</em>`), leaving the browser to guess how to repair it. That kind of error raises nothing at all — the page simply looks wrong. So this tool scans once with a stack, pushing and popping, and closes whatever is still open at the end.

What happens to tags it does not recognise?

They are kept exactly as they are — not converted, not removed. `[hide]` (reply to view), `[attach]` (attachments) and `[media]` (video) are per-forum extensions with no equivalent outside Discuz, and the tool has no way to know what they should become. Keeping them means the user can see at a glance that something was not converted; deleting them hands back a post with pieces missing, which nothing on screen reveals.

Why did some links not become links?

Because their scheme is `javascript:`, `data:` or similar. The output is going onto a forum or blog, where a clickable `javascript:` link is an XSS entry point. This tool only lets through http, https, ftp, mailto, tel and similar, keeping the text and emitting no `<a>` for anything else.

How many pixels is [size=5]?

Discuz sizes are a 1–7 scale, not pixel values; treating the number as pixels gives `font-size: 7px`, which is unreadable. These are mapped through the values the Discuz templates actually use: 1→12px, 3→16px (the default), 5→24px, 7→48px. An unrecognised step falls back to 16px.

Should line breaks become br?

The forum convention is that a line break is a line break, so that is the default. Some sites already render with `white-space: pre-wrap`, though, and there an extra `<br>` doubles every blank line. If the spacing looks too wide after pasting, turn the option off.

Is my content uploaded?

No. The conversion happens entirely in browser memory; the page makes no requests and works offline.