XML Diff -
Compare Two XML Files Online
Compare two XML files online with a semantic diff that understands the document tree, not just the text. Elements are matched by their identity — a namespace, an id-like attribute, or their content — so reformatting, reordering, and whitespace differences never produce a false diff. What's reported is the changes that actually matter.
Built for SOAP payloads, XSD schemas, and vendor XML you wouldn't paste into a random website: both documents are parsed in your browser, compared in memory, and discarded when you close the tab. No upload endpoint, no logging — safe for credential-bearing XML and internal schemas.
Semantic XML Comparison
Move an element or reindent a document and a plain text diff lights up the whole file as changed, because it only sees characters. Semantic comparison works on the tree instead: it parses both inputs into a DOM, matches elements by identity rather than line number, and reports only the real differences — a changed attribute, edited text, or an element that was genuinely added or removed.
Types of XML Differences Detected
Every change is classified and located with a full element path, so you can scan the result instead of reading line by line. These are the kinds of difference the comparison surfaces.
Attribute changes. When an element keeps its identity but an attribute value differs, the attribute is reported on its own with the old and new value — not buried in a whole-element diff.
Text content changes. Edited text inside an element is detected as a change to that element's value, with surrounding whitespace normalized so reindentation doesn't register as an edit.
Added and removed elements. An element present on only one side is reported as added or removed at its matched position, with its full path so you know exactly where it belongs in the tree.
Added and removed attributes. Attributes that appear or disappear are reported separately from value changes, each named individually — useful for auditing security flags and permissions.
Comments and CDATA. Comments are compared in place and CDATA sections are compared as values, so a changed note or data block shows up as its own difference rather than noise.
XML declaration. Changes to the <?xml?> declaration itself — version or encoding — are detected and reported at the top of the document.
Smart Element Matching
The heart of a semantic XML diff is matching — deciding which element on the left corresponds to which on the right. This runs as a four-stage ladder, falling back gracefully when the stronger signal is absent, and it's namespace-aware throughout: elements are keyed by their namespace URI plus local name, so a prefix rename never breaks a match.
- 01Exact structural match. identical tag, attributes, text, and child subtree
- 02Identity attribute. an auto-detected attribute (id, name, or any value unique across siblings) used to pair elements
- 03Similarity. the same tag whose attributes, text, and child count are the closest match
- 04Tag and position. same-tag siblings paired in order, as a last resort
Beyond Tags: Attributes, Namespaces, And Comments
Element names are only part of an XML document, so the comparison goes further. Attributes are compared individually — added, removed, and changed attributes are reported separately from the elements that carry them, each with its old and new value — and attribute order is normalized so a reordered attribute list isn't mistaken for a change. Text content and CDATA sections are compared as values, not as raw markup.
It is namespace-aware, matching elements by their namespace URI and local name so a changed prefix (ns:item versus item) doesn't cascade into false diffs. Comments are compared in place, and changes to the XML declaration itself are detected. The result is a comparison that reads like a review of the document, not a wall of red and green lines.
Sort, Filter, And Navigate
Once the diff is computed, a few controls make a large result easy to read instead of scrolling through unchanged elements.
Sorted Or Input Order. View the comparison with elements and attributes sorted for the cleanest read, or switch to original input order to see each document exactly as you pasted it.
Filter By Change Type. Show all differences, or narrow to only additions, removals, or changes — useful for answering one question, like "what was removed?", without the rest of the noise.
Click To Jump. A side list of every difference lets you click one and jump straight to that element in both documents, then edit in place to resolve it without leaving the page.
How To Compare Two XML Files Online
Four steps to diff XML online and find every real difference between two documents, with no false positives from whitespace or element reordering.
- 01Add Original XML. Paste or upload your first XML into the left editor. It's validated as you type, and any parse error is flagged with its line and column before comparing.
- 02Add Changed XML. Paste or upload the second document on the right. Both are parsed into DOM trees in your browser, and elements are matched by the priority ladder — nothing is sent anywhere.
- 03Review Differences. Changes are categorized — attribute, text, added, removed, comment, declaration — each colour-coded and tagged with its full element path.
- 04Navigate And Fix. Click any difference to jump to the exact element in both documents, then edit in place. Save the comparison or share it through a self-contained link.
Why Use This XML Comparison Tool
An XML diff checker that works on the document tree, runs entirely in the browser, and separates real changes from formatting noise. Eight things make it stand out:
- 01Semantic, Tree-Based Diff. Elements are matched by identity, not position, so reordering a list or reformatting a file no longer creates a wall of false differences.
- 02Auto-Detected Identity Matching. When siblings share a unique attribute — an id, name, or key — it's detected automatically and used to pair elements, even across reordering or insertion.
- 03Namespace-Aware. Elements are keyed by namespace URI and local name, so a changed prefix doesn't cascade into spurious diffs across the whole document.
- 04Attribute-Level Detail. Added, removed, and changed attributes are reported separately from element changes, each with its name and old and new values — ideal for auditing security attributes.
- 05Deep Recursive Comparison. Nested elements, text, CDATA, and comments are compared at any depth, and each difference carries its full XPath-like location like /catalog/book[3]/author.
- 06Sort, Filter & Jump. Toggle sorted or input order, filter to one change type, and click any difference to jump to that element in both documents.
- 07Inline Parse Errors. Invalid XML is flagged in the editor with its line and column, so you fix the syntax before diffing instead of guessing what broke.
- 08100% Private & Free. Your XML never leaves the browser tab — no upload, no logging, no account. Safe for SOAP payloads and internal schemas, free for personal and commercial use.
What This XML Diff Viewer Handles
Any well-formed XML. These are the situations where a semantic XML diff makes the biggest difference in day-to-day work.
Configuration Files
XML config is still the default in Java, .NET, and many enterprise stacks. Diff configs between environments, branches, or versions to find exactly which setting changed.
- web.config and app.config diffs
- Maven pom.xml dependency changes
- Spring XML bean definitions
- log4j configuration drift
- Tomcat server.xml comparisons
API & SOAP Messages
SOAP and XML-RPC payloads are verbose by nature, which makes a text diff unusable. Semantic comparison cuts through the noise and shows only the fields that changed.
- SOAP request and response diffs
- WSDL version comparisons
- XML-RPC payload investigations
- RSS and Atom feed audits
- OFX and financial message diffs
Schemas & Documents
Compare schemas, transformations, and document markup — review XSD updates, compare two XSD files, diff XSLT stylesheets, and audit SVG exports between iterations.
- XSD schema and xsd-vs-xml audits
- XSLT transformation diffs
- SVG export comparisons
- DocBook and DITA document diffs
- Android manifest file reviews
Frequently Asked Questions
How do I compare two XML files online?
Paste the first XML in the left editor and the second in the right, or upload .xml files into either side. Both documents are parsed, elements are matched by identity, and every difference is shown by type with its full element path. Click any diff to jump to that element in both documents.
How does semantic XML comparison work?
Both documents are parsed into DOM trees and walked side by side. Elements are matched through a four-stage ladder — exact structural match, then an auto-detected identity attribute, then similarity of attributes and content, then same-tag position as a fallback. Reordered elements and reformatted documents therefore produce no false diffs.
What if my XML elements don't have IDs?
The matcher falls through the ladder automatically. With no usable identity attribute, it matches by structural and content similarity, and finally by tag and position. That gives good results for most real-world XML without you having to add identifiers.
Does it handle namespaces?
Yes. Elements are keyed by their namespace URI plus local name, so two documents that use different prefixes for the same namespace are compared correctly, and a prefix rename doesn't show up as a change across the whole tree.
Does it detect attribute changes?
Yes. Added, removed, and changed attributes are reported separately from element changes, each with the attribute name and its old and new values — which makes it easy to audit security-sensitive attributes like access controls and permission flags.
Can it compare XSD schemas, WSDLs, or SVG files?
Yes. XSD, WSDL, SVG, XHTML, and POM files are all valid XML, so the same matching and comparison apply. It's especially useful for reviewing API contract changes and comparing two XSD files, where a text diff would be noisy but a semantic XML diff stays clean.
Can it compare deeply nested XML?
Yes. Comparison is recursive at any depth, and each difference reports its full element path, like /catalog/book[3]/author, so you can locate the change precisely in your source document.
Why doesn't reordering show as a difference?
Because in most XML formats element order carries no meaning — a config with the same settings in a different order is semantically identical. The diff matches by identity rather than position, so reordering is treated as a no-op. If order does matter for your case, a plain text diff is the better fit.
What's the difference between comparing XML and JSON?
They're the same idea applied to different tree structures: a semantic diff matches nodes by identity and ignores formatting. XML adds attributes, namespaces, and comments, while JSON deals in keys, arrays, and types. If you're working with JSON instead, use the dedicated JSON diff tool, which is order-independent and type-aware.
Is my XML private and secure?
Yes. The entire comparison runs in your browser; your XML is never uploaded, stored, or sent to a server to be diffed. That makes it safe for SOAP payloads with credentials, internal schemas, and vendor documents under NDA.
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