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Data & formats

XML Studio

Format XML, diagnose well-formedness, inspect namespaces, and test XPath expressions.

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Result0 characters
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XML has layers of validity

XML Formatter, Validator, Tree Viewer & XPath Tester Online

Readable indentation is only the first layer. A reliable workflow distinguishes parse errors, schema rules, namespace context, and query results.

Follow the document from text to matched node

  1. 1

    Source

    Encoded markup and declarations

  2. 2

    Well-formed XML

    Balanced elements, quoted attributes, one root

  3. 3

    Namespace-aware tree

    Expanded names, attributes, text nodes

  4. 4

    Schema validity

    XSD types, order, occurrence, constraints

  5. 5

    XPath result

    Nodes selected in an explicit context

Well-formed is not the same as valid

01 / PARSER

Well-formed XML

A parser can build one unambiguous XML document.

02 / SCHEMA

Schema-valid XML

The document also satisfies the vocabulary and types defined by its XSD.

<invoice total="ten"/> may be well-formed while violating an XSD decimal type.

NAMESPACE CONTEXT

Prefixes are aliases, namespace URIs are identity

The same namespace can use different prefixes. XPath queries need an explicit prefix-to-URI map even when the source uses a default namespace.

Prefix map
inv → urn:example:invoicexsi → http://www.w3.org/2001/XMLSchema-instance//inv:item[@status="open"]

External entities are a security boundary

DevSexy does not fetch external DTDs, schemas, or entity URLs while parsing. This avoids turning a formatter into an XXE or network-discovery client.

● External entity resolution: disabled

● Input processing: browser-local

Pair the document with the right authority

TaskRequired inputOperation
Make it readableXML onlyFormat
Check grammarXML onlyWell-formedness
Check business vocabularyXML + XSDSchema validation
Select nodesXML + namespace mapXPath

XML tooling questions

01Does formatting validate an XML document?
Formatting requires parseable input, but it does not prove conformance to an XSD or business vocabulary.
02Why does my XPath return no results?
A default namespace is a common cause. Bind its URI to a query prefix and use that prefix in the expression.
03Will the tool load an external schema URL?
No. External resource resolution is disabled; provide the schema content directly when schema validation is supported.

Run a reproducible example

Separate well-formed XML from schema validity, then try an XPath query against a local document.

Using an example replaces the current input, reference input, operation, and options. Public demonstration data only.

Check XML syntax without a schema

Validate with an empty reference pane. This checks well-formedness only.

Input

<note><message>Hello</message></note>

The receipt asks for a local XSD before claiming schema validity.

Well-formed XML
Add an XSD

Select one item by attribute

XPath //item[@id="2"]/text() selects the second item from this namespace-free document.

Input

<items><item id="1">Ada</item><item id="2">Lin</item></items>

The query returns Lin; no external document is fetched.

Lin

Continue with a related task

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Repeat the task in DevSexy for Mac

Use the native app for repeated offline work and direct Option shortcuts.

Direct answer

What is XML Studio?

Format and validate XML online, distinguish well-formedness from schema validity, inspect namespaces, test XPath, and keep XXE-sensitive documents off a server.

What can it do?

  • Format
  • Minify
  • Validate
  • Tree
  • XPath

How to use XML Studio

  1. 01

    Prepare the input

    Paste the XML and, for contract validation, its local XSD in the reference pane.

  2. 02

    Choose the operation

    Choose Validate or XPath and supply the expression appropriate to your namespaces.

  3. 03

    Review the evidence

    Distinguish a syntax result, an XSD result, and a query result; they answer different questions.