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60+ free developer tools that run entirely in your browser — JSON formatter, JWT decoder, Base64, diff checker, regex tester, hash generator and more. No upload, no sign-up, completely private.

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Popular Guides

  • How to Format and Pretty-Print JSON (Without Breaking It)
  • How to Minify JSON and Shrink Your API Payloads
  • How to Validate JSON and Pinpoint the Exact Syntax Error
  • How to Convert JSON to CSV for Excel and Google Sheets
  • How to Convert CSV to JSON (With Proper Header Detection)
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© 2026 filemarkr. Designed & developed by Naved Naik.  All processing happens locally in your browser.

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XML Formatter

Pretty-print and indent XML, or collapse it back into one line.

100% private Instant, in-browser Read the guide
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Format, minify and validate XML

The XML Formatter cleans up XML two ways. Beautify mode indents elements by depth so a wall of nested tags becomes a readable tree, and minify mode collapses the whitespace between tags to shrink the document back to a single compact line. As you work it also checks that the input is well-formed and reports the byte size of the result, plus how many bytes minifying saved.

How it works

Paste your XML and the tool tokenizes and re-indents it in your browser, then validates it with the browser's built-in DOMParser. Everything runs in JavaScript on your own machine — there is no upload — so configuration files, SOAP payloads and data feeds never leave the page. Any well-formedness error is surfaced with a readable message so you can find the problem quickly.

Where it helps

  • Make a compact API response or config file readable before editing it.
  • Minify XML to reduce payload size for transport or storage.
  • Catch unclosed tags and mismatched elements through the validation check.
  • Prepare tidy XML snippets for documentation or bug reports.

It sits alongside the other structured-data tools. Convert documents with XML to JSON or go the other way with JSON to XML, and clean up markup with the HTML Beautifier when you are working with tag soup.

The XML Formatter is free, needs no account and works in every modern browser, including mobile. Because all processing is client-side, your XML stays private on your device.

Frequently asked questions

It checks that the XML is well-formed using the browser's DOMParser and shows a readable error if a tag is unclosed or mismatched. It does not validate against a DTD or XSD schema.

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SQL Formatter

Format and beautify SQL queries across MySQL, Postgres and more dialects.

HTML Beautifier

Format and indent messy HTML into clean, readable markup.

CSS Beautifier

Beautify and indent CSS with consistent spacing and formatting.

JavaScript Formatter

Format and beautify JavaScript with proper indentation and spacing.