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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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CSS Beautifier

Beautify and indent CSS with consistent spacing and formatting.

100% private Instant, in-browser Read the guide
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Make messy stylesheets readable again

The CSS Beautifier reformats cramped or minified CSS into clean, consistently spaced rules. Selectors, braces and declarations are placed on their own lines with even indentation, so a compacted stylesheet becomes easy to read and edit. It is the quickest way to bring order to CSS that was minified, generated by a build tool or pasted from somewhere it did not format well.

How it works

Paste your CSS and the tool beautifies it directly in your browser using JavaScript. Nothing is uploaded — your styles are processed locally on your own machine — so proprietary design tokens and unreleased UI code stay private. The formatted stylesheet appears alongside your input, ready to copy back into your project.

When it comes in handy

  • Read and edit a minified .css file that arrived on a single line.
  • Normalize spacing and indentation across a stylesheet before a code review.
  • Clean up CSS copied from a page inspector or a third-party component.
  • Make generated utility CSS understandable before you tweak it.

It complements the rest of the front-end toolkit. When you are ready to ship, shrink the file with the CSS Minifier, format the surrounding markup with the HTML Beautifier, or build new backgrounds with the CSS Gradient Generator.

The CSS Beautifier is free, needs no sign-up and runs in every modern browser, including mobile. Because all formatting happens client-side, your stylesheets never leave the page.

Frequently asked questions

No. It only adds line breaks, spacing and indentation for readability. The selectors, properties and values are unchanged, so the visual result stays the same.

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.

HTML Beautifier

Format and indent messy HTML into clean, readable markup.

JavaScript Formatter

Format and beautify JavaScript with proper indentation and spacing.