Format and validate XML with indented hierarchy and a minify mode for feeds, sitemaps, and configs, with a 500 KB input limit and fully offline processing.
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Quick answer: XML Formatter — Format & validate XML Free, no signup, runs in your browser. See below for the interactive tool, 4-step guide and FAQs.
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Yes, for well-formedness only. It uses the browser DOMParser and shows a generic invalid-XML message when parsing fails, without line or column details or schema validation. Inputs above 500 KB are rejected, so split very large feeds before formatting.
Yes. Minify removes whitespace between tags, producing a compact line while preserving text and attributes. The exact saving depends on how much indentation the source contains, and all processing stays in this tab with no upload. Test the compact output in the target feed reader or sitemap validator before publishing.
Yes. Namespace prefixes such as sitemap:loc are preserved in the output. A normal sitemap formats hierarchically, but the tool checks well-formedness only, not the sitemap schema, and rejects input above 500 KB. Fix structural faults, then copy the result for Search Console inspection. JSON alternatives live at /json-formatter.
XML supports attributes, namespaces, mixed content and schema validation suited to sitemaps and RSS, while JSON favors concise objects for APIs. For example, sitemap loc needs namespace context that JSON lacks. Choose XML for document fidelity, JSON for browser payloads. Unlike the formatter at /json-formatter which enforces braces, this path honors closing tags.
Indentation uses two spaces per nesting level. Formatting indents element hierarchy for feeds, sitemaps and configuration files. Example: a short note with a nested to element expands to indented lines that reveal parent-child ties. Minify collapses whitespace between tags for transport, and namespace prefixes remain intact. The tool validates well-formedness through the browser parser, then serializes the document; it does not check a schema. Well-structured output is easier to diff and review, and the 500 KB limit keeps very large payloads out of the editor.
Reference behavior table: well-formed indents cleanly | unclosed tag triggers a generic parse error | missing quotes fail parsing | namespace prefixes are preserved | minify removes inter-tag whitespace | input above 500 KB is rejected. The error banner does not report a line or column. Edge case: HTML void syntax without closers fails strict parsing, demanding explicit end tags. Namespace prefixes such as sitemap loc are preserved. Validate sitemaps before Search Console submission, test feeds in readers, and monitor encoding declarations to avoid mojibake across locales. Test malformed samples against a validator and keep a known-good copy before editing production feeds.
Paste note to Ada markup, press Format for pretty hierarchy, toggle Minify for single-line transit, copy into feed file. Second trial: validate a 100-URL sitemap, confirming hierarchy and loc entries intact. The formatter round-trips through the browser XMLSerializer, so namespace declarations, attributes and comments survive. A document that parses can still fail a DTD, XSD or sitemap schema check, so use a dedicated validator for structural rules. Minify removes only whitespace between tags; text content and CDATA sections are left intact. Processing never sends markup to a server, and the input box clears only when you paste over it. The browser parser rejects duplicate attributes, mismatched end tags and undeclared entity references; it does not validate attribute order or element meaning. Limitation: strict closure and quoting only; HTML leniency, JSON braces and binary content fall outside scope. For JSON hierarchies, see the formatter at /json-formatter. Keep a backup before editing production files, because formatting can reveal structural faults but cannot repair them automatically.