XML Formatter

Getting Started

Follow these simple steps to format, validate, and edit XML data online:

• Step 1: Switch to the Utility tab at the top of the page.
• Step 2: Paste or type your XML data into the Raw XML panel on the left.
• Step 3: Click the right arrow between the panels to sync the raw XML into the interactive Tree View.
• Step 4: Edit content, attributes, or structure in either panel. Use the left arrow to sync tree edits back to raw XML.

Formatting & Minifying XML

Use the toolbar buttons above the Raw XML panel to transform your XML:

• Format (Pretty Print) — Reformats your XML with proper indentation (2 spaces per level), making nested elements easy to read. Ideal for beautifying minified XML or cleaning up messy markup.
• Minify — Compresses your XML by removing unnecessary whitespace between tags. Reduces file size for storage or transmission while keeping the document valid.

Example: Sample XML

Try pasting this sample XML to explore the formatter features:

• <catalog>
  <book id="1" genre="fiction">
    <title>The Great Gatsby</title>
    <author>F. Scott Fitzgerald</author>
    <year>1925</year>
    <price currency="USD">12.99</price>
  </book>
  <book id="2" genre="science">
    <title>A Brief History of Time</title>
    <author>Stephen Hawking</author>
    <year>1988</year>
    <price currency="USD">15.99</price>
  </book>
</catalog>

After pasting, click the sync arrow to see it rendered as a collapsible tree. Try clicking a text value to edit it, or double-clicking an attribute to modify it.

XML Validation

Validation happens automatically using the browser's built-in DOMParser. The editor provides instant feedback:

• Valid XML — The tree view renders the parsed document structure with collapsible elements, text nodes, comments, and CDATA sections.
• Invalid XML — An inline error appears at the exact line where the syntax problem is, describing the issue (e.g., unclosed tag, mismatched element names, invalid character).

Common XML errors include unclosed tags, mismatched opening and closing tag names, missing root element, and unescaped special characters like &, <, and > in text content.

Tree View Editing

The interactive tree view lets you edit XML visually without writing raw markup:

• Edit Text Content — Click any text node to edit its content inline.
• Edit Attributes — Double-click any attribute to modify its name or value.
• Edit Comments — Click a comment node to update its text.
• Edit CDATA — Click a CDATA section to modify its content.
• Duplicate Nodes — Hover over a node and click the duplicate button to create a copy of the element and all its children.
• Remove Nodes — Hover over a node and click the remove button to delete it from the tree.
• Expand / Collapse — Click the arrow next to any element to expand or collapse its children. Use "Expand All" and "Collapse All" buttons to control all nodes at once.

Syncing Between Panels

The Raw XML and Tree View panels are linked through the sync gutter in the center:

• Right arrow — Parses the raw XML and renders it in the tree view. Use this after pasting or editing raw XML.
• Left arrow — Serializes the tree back to formatted raw XML. Use this after making edits in the tree view.

Syncing is manual so you can make multiple edits before committing changes to the other panel.

Search

Both panels include a search field to help you find elements, attributes, or text within your XML:

• Raw XML Search — Highlights matching text in the raw editor. Use it to find specific tag names, attribute values, or text content.
• Tree View Search — Filters and highlights matching nodes in the tree. Matching element names, attributes, and text content are visually emphasized.

File Operations

Use the toolbar buttons to manage your XML files:

• Load — Upload an XML file from your device. Supports .xml, .xsd, .xsl, .xslt, .svg, .rss, .atom, .plist, .config, and more.
• Copy — Copy the raw XML to your clipboard with a single click.
• Download — Save the current XML as a .xml file to your device.
• Clear — Reset the editor and start fresh.

Example: Format XML (Pretty Print)

Paste minified XML and click Format to see it transformed into readable, indented output:

Input (minified):

• <users><user id="1"><name>Alice</name><role>admin</role></user><user id="2"><name>Bob</name><role>editor</role></user></users>

Output (formatted with 2-space indentation):

• <users>
  <user id="1">
    <name>Alice</name>
    <role>admin</role>
  </user>
  <user id="2">
    <name>Bob</name>
    <role>editor</role>
  </user>
</users>

Each nested element is indented with 2 spaces per level, and each opening/closing tag appears on its own line for maximum readability.

Example: Minify XML

Click Minify to compress formatted XML by removing all unnecessary whitespace:

Input (formatted, 5 lines):

• <config>
  <host>localhost</host>
  <port>8080</port>
  <debug>false</debug>
</config>

Output (minified, 1 line):

• <config><host>localhost</host><port>8080</port><debug>false</debug></config>

Minification removes indentation, newlines, and whitespace between tags while preserving text content and attributes. This reduces file size for network transmission or storage.

Example: Tree View Editing Walkthrough

Here is a step-by-step walkthrough of editing XML in the tree view:

• Step 1: Paste <book id="1"><title>The Great Gatsby</title><price>12.99</price></book> into the Raw XML panel.
• Step 2: Click the right arrow in the sync gutter to load the tree view. You will see a "book" element with an "id" attribute and two child elements: "title" and "price".
• Step 3: Click the text 12.99 next to "price". It becomes editable. Type 14.99 and press Enter.
• Step 4: Double-click the attribute value 1 next to "id". It becomes editable. Change it to 42 and press Enter.
• Step 5: Hover over the "title" node. Click the duplicate button to create a copy of the element.
• Step 6: Edit the duplicated "title" text to Tender is the Night — now you have two title elements.
• Step 7: Hover over the duplicated title and click remove to delete it.
• Step 8: Click the left arrow to sync your changes back to the Raw XML panel.

The tree view preserves the document structure and node types throughout editing. Element names, attributes, text content, comments, and CDATA sections are all editable inline.

Node Types in the Tree View

The tree view renders all standard XML node types with distinct visual styling:

• Elements — Shown as collapsible nodes with the tag name in angle brackets (e.g., <book>). Elements with children show a collapse/expand arrow and a child count (e.g., "3 children"). Elements with only text content are rendered as leaf nodes showing the tag name and text value on a single line.
• Attributes — Shown inline next to the element name in a name="value" format. Double-click any attribute value to edit it. Attribute names are read-only.
• Text Nodes — Shown as leaf nodes with the text content. Click the text to edit it inline. Whitespace-only text nodes are hidden to keep the tree clean.
• Comments — Shown as <!-- comment text --> with gray styling. Comments are displayed as leaf nodes in the tree.
• CDATA Sections — Shown as <![CDATA[ content ]]> with gray styling. CDATA sections preserve their content exactly as written, without XML parsing.

Keyboard Shortcuts

The XML formatter supports keyboard navigation for efficient editing:

Raw XML Editor:

• Tab — Inserts 2 spaces at the cursor position (instead of moving focus). This makes it easy to indent XML manually in the text area.

Tree View Navigation:

• Arrow Down / Arrow Up — Move focus to the next or previous visible node in the tree. Collapsed children are automatically skipped.
• Arrow Right — Expand the currently focused element to reveal its children.
• Arrow Left — Collapse the currently focused element to hide its children.
• Enter — Start editing the text content of the currently focused node.
• Delete — Remove the currently focused node from its parent element.

Inline Editing (when editing text or attributes):

• Enter — Commit the edit and stop editing.
• Escape — Cancel the edit and revert to the previous value.
• Tab — Commit the current edit and move to the next editable field.
• Shift + Tab — Commit the current edit and move to the previous editable field.

Syntax Highlighting

The raw XML editor includes real-time syntax highlighting to make your XML easier to read. Different elements are color-coded:

• Tag names — Displayed in blue, including the angle brackets (< and >).
• Attribute names — Displayed in orange to distinguish them from tag names.
• Attribute values — Displayed in green, including the surrounding quotes.
• Comments — Displayed entirely in gray (<!-- ... -->).
• CDATA sections — Displayed in gray (<![CDATA[ ... ]]>).
• Text content — Displayed in the default text color.

The highlighting updates in real time as you type, and the overlay scrolls in sync with the text area.

Line Numbers

The raw XML editor displays line numbers along the left edge for easy reference. Line numbers update automatically as you type and scroll in sync with the text area. When a validation error occurs, the inline error message references the specific line number where the parser encountered the problem.

Auto-Collapse for Large XML

When you first sync XML to the tree view, nodes deeper than 2 levels are automatically collapsed to keep the tree manageable. This is especially useful for large XML documents with deeply nested structures. You can expand any collapsed node by clicking its arrow or pressing the Right Arrow key. After the first render, the tree preserves your expand/collapse state across re-renders.

Use Cases for XML Formatting

Our free XML formatter online is useful for developers, data analysts, and anyone working with XML data:

• Web Services & APIs — Format and inspect SOAP responses, REST XML payloads, and RSS/Atom feeds to debug integration issues.
• Configuration Files — Edit web.config, pom.xml, AndroidManifest.xml, or other config files with a visual tree for easier navigation.
• Data Exchange — Validate and format XML data files before importing into databases, ETL pipelines, or enterprise systems.
• SVG Editing — Load SVG files (which are XML) to inspect and modify vector graphic structures.
• Learning XML — Students can use the tree view to understand XML document structure — elements, attributes, namespaces, comments, and CDATA sections.

What is XML?

XML (eXtensible Markup Language) is a markup language designed to store, transport, and structure data in a format that is both human-readable and machine-readable. Developed by the World Wide Web Consortium (W3C) in 1998, XML has become a foundational technology for data exchange across the internet and enterprise systems.

Unlike HTML, which has predefined tags for displaying content, XML allows you to define your own custom tags to describe the meaning of your data. This makes XML extremely flexible for representing structured information of any kind.

Key characteristics of XML:

• Self-describing — XML tags describe what the data is, not how it should look. <price currency="USD">29.99</price> clearly conveys both the value and its context.
• Hierarchical — XML documents form a tree structure with a single root element. Child elements can be nested to represent complex relationships.
• Platform-independent — XML is plain text, so it works on any operating system, programming language, or platform.
• Extensible — You create your own tag names and document structure. There are no reserved tag names (unlike HTML).
• Strict syntax — XML requires well-formed documents: all tags must be closed, properly nested, and case-sensitive.

XML Document Structure

Every valid XML document follows a specific structure. Understanding these components helps you write and debug XML effectively:

• XML Declaration — The optional first line that specifies the XML version and character encoding: <?xml version="1.0" encoding="UTF-8"?>.
• Root Element — Every XML document must have exactly one root element that contains all other elements. For example, <catalog>...</catalog>.
• Elements — The building blocks of XML. Each element has an opening tag (<book>), content, and a closing tag (</book>). Empty elements can use self-closing syntax: <br/>.
• Attributes — Additional information attached to elements: <book id="1" genre="fiction">. Attribute values must always be quoted.
• Text Content — The actual data contained within elements: <title>The Great Gatsby</title>.
• Comments — Notes that are ignored by parsers: <!-- This is a comment -->.
• CDATA Sections — Blocks of text that the parser should not interpret as markup: <![CDATA[This <text> is not parsed]]>. Useful for embedding code or special characters.

Common XML Errors and How to Fix Them

XML has strict syntax rules. Here are the most common errors you will encounter and how to resolve them:

• Unclosed tags — Every opening tag must have a corresponding closing tag. <item>value is invalid. Add the closing tag: <item>value</item>.
• Mismatched tag names — Opening and closing tags must match exactly, including case. <Item>value</item> is invalid because XML is case-sensitive. Use <Item>value</Item>.
• Missing root element — An XML document must have exactly one root element. Having two top-level elements like <a/><b/> is invalid. Wrap them in a root: <root><a/><b/></root>.
• Unescaped special characters — Characters like &, <, >, ", and ' must be escaped in text content and attribute values. Use &, <, >, ", and ' respectively.
• Improper nesting — Elements must be properly nested. <a><b></a></b> is invalid. Correct nesting: <a><b></b></a>.
• Unquoted attribute values — All attribute values must be enclosed in quotes (single or double). <item id=5> is invalid. Use <item id="5">.
• Invalid characters in element names — Element names cannot start with a number, contain spaces, or include special characters (except hyphens, underscores, and periods). <1item> and <my item> are both invalid.

Paste your XML into our formatter to instantly see the exact line and description of any syntax error.

Where is XML Used?

Despite the rise of JSON for web APIs, XML remains essential in many industries and technologies:

• Web Services — SOAP APIs use XML for request and response messages. WSDL files that describe web services are written in XML.
• Data Feeds — RSS and Atom feeds use XML to syndicate blog posts, news articles, and podcast episodes.
• Configuration — Enterprise applications use XML config files: web.config (ASP.NET), pom.xml (Maven/Java), AndroidManifest.xml (Android), and .csproj (C#/.NET).
• Document Formats — Microsoft Office files (.docx, .xlsx, .pptx) are ZIP archives containing XML documents. SVG vector graphics are XML-based.
• Data Exchange — Industries like healthcare (HL7/FHIR), finance (FIX/FpML), and government use XML for standardized data exchange between systems.
• Publishing — DocBook and DITA are XML-based formats used for technical documentation and book publishing.

XML Best Practices

Follow these best practices to write clean, maintainable XML:

• Always include the XML declaration — Start every document with <?xml version="1.0" encoding="UTF-8"?> to specify version and encoding explicitly.
• Use meaningful element names — Choose descriptive names like <customerName> instead of <cn>. XML is self-documenting when tag names are clear.
• Be consistent with naming — Pick a convention (camelCase, PascalCase, or kebab-case) and use it consistently throughout the document.
• Prefer elements over attributes for data — Use attributes for metadata (IDs, types, roles) and elements for actual data content. This makes the document easier to extend.
• Use indentation for readability — Format your XML with consistent indentation (2 or 4 spaces) during development. Use our formatter to automatically apply clean indentation.
• Validate against a schema — Use XSD (XML Schema Definition) or DTD (Document Type Definition) to validate your XML structure when working with standardized formats.
• Escape special characters — Always escape &, <, and > in text content. Use CDATA sections for large blocks of text containing many special characters.

Privacy

Your XML data is processed entirely in your browser using JavaScript. Nothing is ever sent to any server — your data stays on your device, always. There is no tracking, no account required, and no data collection of any kind. Learn more in our Privacy Policy.

Frequently Asked Questions

How do I format XML online for free?

Paste your XML into the Raw XML panel and click the Format button. The XML will be pretty-printed with proper indentation. The tree view updates automatically to show the structured document.

How do I validate XML online?

Paste or type XML in the editor — validation happens automatically. Valid XML shows a tree view. Invalid XML shows an inline error at the exact line with a description of the syntax problem.

Can I edit XML in the tree view?

Yes. Click any text content to edit it inline. Double-click attributes to modify them. You can also duplicate or remove any node using the action buttons that appear on hover.

Can I minify XML online?

Yes. Click the Minify button to compress your XML by removing unnecessary whitespace between tags. This reduces file size while keeping the document valid.

Is my XML data safe in this online formatter?

Your XML never leaves your device. All parsing, formatting, and validation happens locally in your browser — no data is sent to any server. Learn more in our Privacy Policy.