XML Formatter

Indented 1 line(s) of XML at 2-space depth.

How it works

• Tokenised elements, attributes, comments, CDATA and processing instructions.
• Tracked the element stack and reported the first mismatched or unclosed tag.
• Emitted each element on its own line at a depth-based indent.

• XML is strictly nested, so the formatter can prove well-formedness while formatting.
• Output is 5 line(s); formatting it again changes nothing.

Methodology

1. Tokenise elements, attributes, comments, CDATA and processing instructions with a quote-aware scanner.
2. Maintain an element stack; a close tag must match the most recent open tag and the stack must be empty at the end.
3. Emit each element on its own line at a depth-based indent.

Usage

1. Paste or type a well-formed XML document.
2. Choose a 2- or 4-space indent.
3. Run the formatter; malformed nesting is reported with a location.

Examples

These are examples, not current values: they use fixed inputs, while the interactive tool computes live results in your browser.

Nested elements

{
  "text": "<root><item id=\"1\">x</item></root>",
  "indentSize": 2
}

Self-closing tag

{
  "text": "<root><a/><b/></root>",
  "indentSize": 4
}

CDATA preserved

{
  "text": "<root><![CDATA[a < b]]></root>",
  "indentSize": 2
}

Limitations

Well-formedness is the contract

Unlike HTML, XML must nest exactly. The formatter uses that strictness to validate structure while it indents, so a syntax error is surfaced rather than hidden.