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XML Formatter
Paste any XML – minified, one-line, or malformed-looking – and get it back as clean, indented, human-readable markup with validation feedback.
✓ Free✓ No signup✓ Privacy first✓ Runs in your browser
XML Formatter & Validator - ToolPremier
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XML Formatter & Validator · parsing done entirely client-side · 100% private

How it works
Convert in three steps

1. Paste your XML

Drop in any XML string - an API response, a config file, a sitemap, an RSS feed, or a raw one-liner. Minified or formatted, it works either way.

2. Format and validate

The formatter indents the XML with consistent whitespace and validates the structure. Errors like unclosed tags or malformed attributes are flagged with line references.

3. Copy the formatted output

Get clean, indented XML ready to read, diff, or use in documentation and config files.

FAQ
Common questions
Formatting only changes the visual presentation – indentation and whitespace – without checking whether the XML is structurally correct. Validation checks that the XML is well-formed (properly nested tags, closed elements, correct attribute syntax) and optionally validates against a schema (DTD or XSD). This tool formats and checks for well-formedness – it does not validate against external schemas.
Common well-formedness issues include: unclosed tags, attribute values not wrapped in quotes, special characters not properly escaped (& must be &, < must be <), and multiple root elements (XML requires exactly one root element). The formatter flags the specific line and issue so you can fix it directly.
Both are data serialization formats, but XML supports attributes and mixed content which JSON does not. XML is more verbose than JSON for the same data, but it is still widely used in enterprise systems, SOAP APIs, configuration files, sitemaps, RSS/Atom feeds, and office document formats (DOCX, XLSX are ZIP archives of XML files).
Yes. RSS feeds and XML sitemaps are valid XML documents and format correctly with this tool. This is useful for debugging a sitemap that is not being read correctly by search engines or an RSS feed that is not rendering in feed readers – formatting often reveals structural issues that were not visible in a one-line raw output.
Keep going
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About the XML Formatter
XML is still in heavy use across enterprise APIs, configuration systems, sitemap files, RSS feeds, and office document formats – and it is rarely received in a readable state. API responses come as one-liners, configuration exports are minified for transport, and RSS feeds from CMS platforms vary wildly in formatting. This formatter parses the XML and outputs it as properly indented, consistently structured markup, making it readable for review and easy to diff between versions. It also checks well-formedness as part of the format pass, so structural errors – unclosed tags, unescaped characters, missing attribute quotes – are surfaced with line references rather than silent failures.
Benefits
  • Formats any valid XML - API responses, config files, sitemaps, RSS feeds, SOAP payloads.
  • Well-formedness validation - unclosed tags and syntax errors flagged with line references.
  • Consistent indentation - clean, uniform output regardless of how the input was structured.
  • Client-side processing - XML data with internal config values never leaves your browser.
Privacy
All XML formatting runs in your browser. XML content is never uploaded or transmitted to any server.