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Format, beautify and minify XML documents. Validate XML syntax with helpful error messages.
Key rules:
vs JSON:
Common XML uses:
Browser XML parsing has memory limits – very large files (over 100 MB) may slow or fail. Doesn’t validate against external schemas (XSD) – just basic well-formedness. For schema validation, namespace handling, or XSLT transformations, use dedicated libraries. The minified output is unindented but still parses – some ‘aggressive’ minifiers remove additional content but risk breaking semantics.
JSON for APIs and data exchange (smaller, simpler, native to JavaScript). XML for documents (Office files, RSS feeds, SVG graphics) and legacy enterprise (SOAP APIs, configuration files). Modern web development almost always uses JSON. XML still essential for specific use cases.
Common causes: (1) Unclosed tags. (2) Multiple root elements. (3) Special characters not escaped (use & for &). (4) Mismatched tag case. (5) Quote mismatch in attributes. (6) Missing XML declaration. Tool shows the specific error – fix and re-validate.
XML is for data – any tag names you define, must be strictly well-formed. HTML is for documents – predefined tag set (<div>, <p>, etc), browsers are lenient with errors. XML follows strict rules; HTML is forgiving. XHTML is a stricter HTML variant following XML rules.
Five reserved characters need escaping: & → &, < → <, > → >, ‘ → ', ‘”‘ → ". Always escape these in text content and attribute values. For large unescaped chunks, use CDATA sections.
Yes – parsers built into JavaScript (DOMParser, XMLSerializer). Most often used for: parsing RSS/Atom feeds, generating SVG, reading XML configs, calling SOAP APIs (legacy). JSON is preferred for new APIs but XML isn’t gone.
XSD defines the structure XML files must follow – what tags, attributes, types are allowed. Provides validation: schema-valid XML is guaranteed correct. Used in enterprise systems (banking, government) where data integrity matters. JavaScript browser XML doesn’t typically validate against schemas – server-side does.
Yes for specific cases. Documents (Office formats), SVG, RSS feeds, sitemaps, SOAP banking APIs, Android manifests, Maven build configs – all XML. Less common for new web APIs (JSON dominates). Still tens of billions of XML documents processed daily worldwide.
JSON Formatter · YAML Validator · CSV to JSON