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XML to JSON Conversion Guide: Parsing Nodes & Attributes

August 4, 2026 6 min read Client-Side Privacy
Quick Summary

To convert XML to JSON: Paste XML code into the XML Online Viewer Tool. Click XML to JSON (Alt+6). The client-side parser traverses XML DOM nodes, maps tag attributes and text values into clean JSON keys, and outputs formatted JavaScript objects locally.

Understanding XML vs JSON Data Structures

XML (eXtensible Markup Language) remains widely used in enterprise SOAP services, RSS feeds, and legacy APIs. Modern web applications prefer JSON due to its native compatibility with JavaScript. Converting XML payloads to JSON requires parsing node attributes, handling repeating sibling nodes as arrays, and stripping whitespace text nodes.

How Browser DOMParser Parses XML

Our client-side conversion engine relies on the native browser DOMParser API to construct a validated document object tree:

// Browser DOMParser XML Validation Engine const parser = new DOMParser(); const xmlDoc = parser.parseFromString(xmlString, "text/xml"); if (xmlDoc.getElementsByTagName("parsererror").length > 0) { throw new Error("Invalid XML document syntax"); }

Handling Node Attributes and Child Elements

During conversion, XML attributes like id="101" are prefixed with @ or mapped into property keys so that zero structural context is lost during transformations.

Prettifying and Minifying XML Files

In addition to JSON conversion, the tool provides instant tag formatting with 2-space indentation (press Alt+1) and XML minification (press Alt+2) for optimizing payload file sizes.