Free Online XML Diff Tool

Instantly Compare XML Visually

A semantic XML diff tool that understands hierarchical structure — not just text. Detect element changes, attribute modifications, and missing nodes with full path context.

Base XML

Contrast XML

Features

A client-side XML comparison tool that parses structure semantically — not just text. Fast, private, and free for developers working with XML data.

Semantic Diff Visualization

Color-coded highlights for every difference: green for additions, red for deletions, yellow for modifications. Full element-path reporting for nested XML structures.

Instant Comparison

Efficient recursive algorithms compare XML documents with thousands of elements in under a second. No server round-trip, no loading spinners.

100% Client-Side & Private

All XML parsing and diffing happens in your browser using JavaScript. Your data never leaves your device — zero server uploads, zero logging.

How to Compare XML

Start comparing XML documents in three simple steps — no installation or signup needed.

01

Enter Your XML

Enter or paste two XML documents into the left (Base) and right (Contrast) editor panels. You can also drag-and-drop files or import from a URL.

02

Run the Comparison

Click the 'Compare' button. The tool instantly parses both inputs, normalizes structure, and produces a semantic diff.

03

Review the Diff Results

View color-coded diff results with additions, deletions, and modifications highlighted inline. Navigate differences by category in the sidebar.

How Semantic XML Comparison Works

Unlike text-based diff tools, our XML comparator understands document structure. It parses, normalizes, and recursively compares — so formatting changes and attribute reordering never produce false diffs.

01

Parse & Normalize XML

Both XML inputs are parsed into hierarchical tree structures using fast-xml-parser. Elements and attributes are organized into a normalized object representation — so whitespace differences never create false positives.

02

Recursive Node Comparison

The algorithm traverses both XML trees recursively, comparing elements at each level. It detects added/deleted elements, attribute changes, and text content modifications at every nesting level.

03

Repeated Element Matching

Repeated child elements can be matched using three strategies: By Index (positional), LCS (Longest Common Subsequence for intelligent insertion/deletion detection), and Unordered (set-like comparison ignoring element order).

04

Visual Diff Rendering

Each difference is mapped to its source position in the XML and rendered with color-coded highlights — green for additions, red for deletions, yellow for modifications — with full element path context.

Use Cases

XML comparison is essential across many development and data workflows.

API & SOAP Services

Compare XML request/response payloads for SOAP web services, REST APIs with XML responses, or WSDL definitions. Verify endpoint behavior during development, QA, and automated CI/CD pipelines.

Configuration File Diff

Track changes between XML configuration file versions — pom.xml, web.xml, Spring configs, Android manifests, or any structured XML config.

Data Transformation Validation

Validate XML data transformations, compare XSLT outputs, or verify data migration results between XML-based systems and databases.

Document Format Comparison

Compare structured documents in XML-based formats like DocBook, DITA, or SVG files where element structure matters.

Load XML Data via URL

Load XML data into the comparison result page by passing URL query parameters. Useful for sharing diff results, CI/CD integration, or linking from documentation.

Load XML from File URL

Pass publicly accessible URLs to the base and contrast parameters. The tool will fetch and compare the XML content from these URLs automatically.

Load XML from Base64

Encode your XML content as a Base64 string and pass it directly in the URL. Use base-64.com to encode/decode your data.

FAQ

01Is my XML data sent to a server?
No. All XML parsing and comparison happens entirely in your browser using JavaScript. Your data never leaves your device — we don't collect, transmit, or store any of the XML you input. The tool works even offline once loaded.
02How does it handle XML namespaces and attributes?
The tool parses both namespaces and attributes correctly. Attributes are compared independently from element content, and namespace prefixes are handled in the parsed tree structure.
03What about large XML documents?
The tool uses an efficient recursive algorithm optimized for hierarchical data. It can handle XML documents with thousands of elements and deeply nested structures, performing comparisons quickly in the browser.
04How are repeated elements compared?
You can choose between three modes: 'By Index' compares elements at the same position, 'LCS' (Longest Common Subsequence) intelligently detects insertions and deletions, and 'Unordered' treats sibling elements as sets — ignoring element order entirely.