How to use it
- Paste code, drop a file or load the sample; the language is preset for this page and can be changed.
- Choose format or minify and adjust indent, width and other options; the result appears on the right as you type.
- Copy or download the result; on an error, use "Go to error", fix it and run again.
Five rules of well-formed XML
The XML is checked before formatting; errors show the line and column, and "Go to error" jumps there.
| Rule | Wrong | Right |
|---|---|---|
| Exactly one root element | <a/><b/> | <root><a/><b/></root> |
| Tags close and nest properly | <a><b></a></b> | <a><b></b></a> |
| Attribute values are quoted | <a x=1> | <a x="1"> |
| Escape special characters | Tom & Jerry | Tom & Jerry |
| Case sensitive | <Item></item> | <Item></Item> |
Languages and engines
Formatting uses the same open-source engines as popular editors, so results match Prettier in VS Code and your team can keep one style. Every engine loads from this site and runs in your browser.
| Language | Format | Compress |
|---|---|---|
| HTML | Prettier 3 | ✓ comments and whitespace |
| XML | XunL XML engine | ✓ |
| CSS / SCSS / Less | Prettier 3 | ✓ CSSO restructuring |
| JavaScript / TypeScript | Prettier 3（Babel） | ✓ Terser (JavaScript only) |
| JSON | Prettier 3 | ✓ big numbers keep precision |
| YAML | Prettier 3 | — (comments kept) |
| SQL | sql-formatter (14 dialects) | — |
Frequently asked questions
Does it validate against an XSD?
It checks that XML is well-formed: tags match and nest, attributes are quoted and there is one root. Validity against an XSD or DTD needs a dedicated validator.
Does formatting change the data?
Elements, attributes and text stay the same; only indentation and line breaks change. Whitespace-only text nodes are dropped and unquoted values get double quotes. Check whitespace-sensitive documents such as xml:space="preserve" first.
Is my code uploaded?
No. The engines download from this site and run in your browser; your code never passes through our servers or any third party, so it is safe for internal code and configuration.
How large can files be?
Up to 5 MB per file; above 300 KB the page waits for the button instead of formatting as you type, to keep the browser responsive.