XML Formatter — Pretty Print, Minify & Validate XML

Developers working on SAML, RSS, SOAP, or Android resources often receive XML that is technically valid but unreadable. A single-line WSDL or pom.xml slows code review and makes merge conflicts harder to spot. Pretty printing restores predictable indentation so element nesting is visible at a glance.

Generic formatters that treat XML as one of several tabs optimize for quick API response inspection. A dedicated XML page invests in DOMParser error messages, indent normalization, and minify behavior tuned for markup — not JSON key sorting or YAML flow styles.

The browser DOMParser builds an in-memory document tree from your string. Pretty print walks that tree and emits tags with line breaks and indent depth proportional to nesting level. Text nodes and CDATA sections preserve content while surrounding tags gain readable structure.

Because serialization happens after parse, malformed input fails before any beautified output appears. That fail-fast behavior prevents accidentally prettifying truncated paste buffer content that looks fine visually but breaks downstream parsers.

Minify strips indent newlines and inter-tag spaces that do not change document meaning. Smaller payloads help when embedding XML in query parameters is impossible but shipping compact config blobs matters — CI artifacts, mobile bundle size exercises, or log aggregation quotas.

Minified XML is harder for humans to read — keep a pretty copy in source control and minify only for release pipelines or size benchmarks. Our tool lets you toggle modes on the same input without re-pasting.

Well-formed XML requires a single root element, matched open and close tags, escaped special characters in text nodes, and legal attribute quoting. DOMParser reports errors for unclosed tags, duplicate attributes, and illegal character references before formatting proceeds.

Validation here means syntactic correctness, not business-rule compliance. An RSS feed missing required channel elements may parse fine while failing feed validators elsewhere. Use this step to catch typos early, then run domain-specific validators for schema rules.

API response formatter accepts JSON, XML, or YAML in one workspace with format conversion shortcuts — ideal when debugging REST clients that return mixed content types. XML formatter goes deep on XML-only indent, minify, and DOMParser diagnostics without JSON tree views or YAML anchors.

Choose API response formatter when switching between response bodies from the same endpoint family. Choose XML formatter when your day is WSDL, Maven POMs, sitemap.xml, or SAML metadata and you want a focused XML toolchain page.

Documents with xmlns declarations and prefixed elements parse into namespaced nodes. Pretty print preserves namespace prefixes on elements and attributes as the serializer emits them — critical for SAML and Atom feeds where prefix consistency matters for signature verification.

CDATA sections keep literal content without entity escaping — useful for embedded scripts or base64 blobs inside XML config. The formatter retains CDATA boundaries rather than converting them to escaped text unless you edit content manually.

Internal integration XML sometimes embeds tenant IDs, endpoint URLs, or certificate hints. Processing locally means those strings never traverse our network. Treat the page like a desktop XML editor without persistence.

Clear the tab or refresh when finished on shared machines. No server-side session stores your paste.

Teams often standardize on two-space or four-space indent in .xml files. Run pretty print before committing so diffs show logical changes instead of whitespace roulette. Minify before comparing byte size against a baseline bundle.

When reviewing pull requests, copy suspicious hunks here to expand minified sections reviewers could not read inline in the diff viewer.

Embedding XML inside HTML attributes or JavaScript strings requires entity encoding beyond formatting. After pretty printing, use html-encoder-decoder when inserting markup into templates. URL-encoding applies when passing XML in query strings — rare and usually discouraged.

Formatting does not escape < for HTML context. Never paste raw formatted XML into innerHTML without encoding.

Generated documents from ORM or build tools may exceed comfortable browser paste limits. Split by logical sections — one schema file at a time — or use command-line formatters for megabyte-scale batch jobs. This page targets interactive editing and spot checks.

If parse errors reference line numbers, split the document near the reported region, fix locally, and merge. DOMParser error detail varies by browser — always fix the first reported error before chasing secondary messages.