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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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HTML Beautifier

Format and indent messy HTML into clean, readable markup.

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Turn minified HTML into readable markup

The HTML Beautifier takes messy, minified or machine-generated HTML and reformats it into clean, properly indented markup. Tags are placed on their own lines and nested by depth, so a single unreadable line becomes a structure you can actually scan. You can choose an indent width of two or four spaces to match your project's style.

How it works

Paste your HTML and the tool formats it in your browser with a well-established JavaScript beautifier. Nothing is uploaded: the markup is processed locally on your machine, which keeps templates, email HTML and any embedded content private. The formatted result appears next to your input, ready to copy or download as an .html file.

Practical uses

  • Make a minified page or an emailed HTML template readable before editing.
  • Clean up markup pasted from a CMS, page builder or scraper.
  • Prepare consistent, indented snippets for documentation or code review.
  • Understand the structure of an unfamiliar component by seeing its nesting.

It works hand in hand with the other web tools. When you are done editing, shrink the file again with the HTML Minifier, tidy the accompanying styles with the CSS Beautifier, or generate markup from a document with Markdown to HTML.

The HTML Beautifier is free, requires no account and runs in every modern browser, including mobile. Since all formatting is client-side, your markup never leaves the page and stays private on your device.

Frequently asked questions

No. It only adds indentation and line breaks to make the markup readable. The tags and content stay the same, so the rendered page is unchanged.

Related tools

SQL Formatter

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

XML Formatter

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

CSS Beautifier

Beautify and indent CSS with consistent spacing and formatting.

JavaScript Formatter

Format and beautify JavaScript with proper indentation and spacing.