Zero Snippet

XML formatter & validator — beautify, minify, and check well-formed XML

Use this free online XML formatter to pretty-print XML with consistent indentation, minify XML for compact payloads, or validate XML syntax before it hits feeds, integrations, or build pipelines. Parsing runs entirely in your browser, so you get fast feedback and actionable parse errors without uploading files. After a successful check, read lightweight structure insight (root element, depth, and tag frequency) to understand large configs and API responses at a glance—ideal for RSS and Atom, legacy SOAP, Android XML resources, SVG stored as XML, and CI templates that must stay syntactically sound.

How to use this XML formatter and validator

Paste any UTF-8 XML document into the input panel, then choose an action. Format / beautify rebuilds the tree with two-space indentation and readable line breaks—great for code review, diffs, and documentation. Minify removes non-essential whitespace between tags while keeping text node content intact, which helps when you need a smaller payload for logs or transport. Validate only confirms well-formed XML (balanced tags, legal entities, single root) and surfaces browser parser messages you can trace back to a line or token. When validation succeeds, the structure card summarizes the document so you can spot unexpected wrappers or duplicated nodes before you ship. Use Copy on the output to grab the result for tickets, chats, or repositories.

When to format XML versus JSON or YAML

Many teams still exchange enterprise XML for invoices, identity protocols, and feed syndication, while newer services prefer JSON or YAML for configs. If you are converting between shapes, start with a clean XML tree here, then use our JSON formatter & validator, YAML to JSON converter, or JSON to YAML converter once payloads are valid in those formats. For markup-heavy content that targets browsers rather than strict XML parsers, the HTML formatter & minifier is usually a better fit than forcing HTML through an XML-only tool.

XML best practices for feeds, APIs, and configs

Declare encoding when files leave your editor (UTF-8 is the modern default) and keep a single document root. Prefer explicit namespaces for mixed vocabularies so consumers do not guess prefixes. When whitespace between elements is meaningful to your domain, diff carefully after minify. Pair syntactic checks with contract tests in your stack for schema-level rules this page does not enforce. If you work alongside web operations, our HTTP header checker and response code checker help verify how XML responses are served over the wire (Content-Type, caching, and status codes).

Privacy and limitations

Formatting and validation execute locally with the same XML parser your browser uses for text/xml documents, so content is not sent to our API for this tool. That makes it appropriate for quick redaction-friendly cleanup, with the usual caveat that anyone shoulder-surfing still sees your screen. This utility confirms well-formedness, not full XSD/DTD/RNG schema compliance. Byte-for-byte canonical output for digital signatures may differ from your source tool’s serializer; verify with your security requirements when signatures matter.

Related developer tools

Explore the full code & developer tools section on the home page, or jump to a related formatter below.

  • JSON Formatter & Validator — Format, validate, minify, and explore JSON in a collapsible tree—fix payloads before they hit production.
  • JSON to CSV Converter — Turn JSON arrays into downloadable CSV with automatic column detection for spreadsheets and BI tools.
  • JSON to YAML Converter — Convert JSON to readable YAML for configs and Kubernetes—copy or download the result.
  • CSV to JSON Converter — Paste or upload CSV and get structured JSON with header-aware typing for APIs and apps.
  • YAML to JSON Converter — Parse YAML to valid JSON with clear errors—ideal for CI configs and cloud templates.
  • Regex Tester & Debugger — Test patterns live with highlights, capture groups, and flags—debug regex without leaving the browser.
  • SQL Formatter — Pretty-print SQL with indentation and keyword casing for readable queries and code review.
  • HTML Formatter & Minifier — Beautify or minify HTML and compare raw markup with a quick rendered preview.
  • CSS Formatter & Minifier — Format messy stylesheets or minify CSS for faster loads—keep design tokens consistent.
  • JavaScript Formatter & Minifier — Pretty-print or minify JavaScript for debugging locally and shipping smaller bundles.

Frequently asked questions

What is the difference between formatting and validating XML?
Formatting (pretty-printing) rewrites your document with consistent indentation and line breaks so humans can read hierarchy quickly. Validation checks whether the browser’s XML parser accepts the document as well-formed XML: every tag is closed, attributes are quoted, entities are legal, and there is a single root element. This tool does both in your browser—no upload to our servers.
Does this tool check XML against an XSD or DTD schema?
No. Well-formedness is enforced by the parser (structure and syntax). Schema validation (XSD, Relax NG, DTD) needs extra rules and often network or local schema files. For configs and APIs, pair this formatter with your stack’s schema tools, or use our JSON and YAML utilities when you convert formats.
Why do I see a parser error for HTML?
HTML is often not valid XML unless it is XHTML or strictly closed. Self-closing tags, unquoted attributes, or void elements like <br> without XML rules will fail. Use our HTML formatter for markup meant for browsers, and reserve this tool for RSS, SOAP, SVG-as-XML, Android layouts, and other XML-first documents.
Will minify change the meaning of my XML?
Minify removes non-essential whitespace between tags. Whitespace inside text nodes is preserved. If your application treats boundary whitespace between elements as significant data, review the minified output before deploying. Most data-exchange XML is whitespace-insensitive between elements.
Is my XML stored or logged?
Processing runs entirely in your browser. Nothing is sent to our API for formatting or validation. Avoid pasting secrets anyway—clipboard and screen sharing are still risks in shared environments.
How do namespaces and prefixes appear after formatting?
The browser keeps namespace declarations and uses qualified names (prefix:localName) where applicable. Declarations may move relative to hand-written order but stay semantically equivalent for parsing. Always verify critical signed documents (such as some SAML assertions) with your security team if byte order matters.
What does structure insight include?
After a successful parse we report the document root element name, total element count, approximate maximum depth, and a frequency table of element tag names. That helps you spot unexpected nodes, duplicated wrappers, or oversized trees before diffing or shipping to production.