Free tool
XSD validator
Validate an XML document against an XSD schema and get every violation with its line — required attributes, datatypes, element order and cardinality.
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Reference for these formats
XML Schema (XSD)
The dominant XML schema language: namespace-aware, richly typed, and itself written in XML — so schemas diff and version-track like the payloads they govern.
SOAP envelope
The message envelope for SOAP web services — still the backbone of banking, logistics and telecom, with its version carried by the namespace URI.
UBL Invoice
The OASIS invoice document behind Peppol and most European e-invoicing mandates, splitting its vocabulary across three namespaces you must all declare.
WSDL
The machine-readable contract for a SOAP service: operations, messages, bindings and endpoints, with an inline XSD describing its own types.
Hit a parse error? Every common XML error explained.
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Get started
Keep the documents you check, and watch them for changes.
A free workspace stores versions, extracts their structure for search, and re-checks monitored URLs on a schedule. Paste or upload up to 4 MB, or fetch a URL up to 5 MB.