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JS, CSS & HTML Code Studio

Minify, mangle, or beautify JavaScript (via Terser AST), CSS, and HTML in your browser with instant raw, minified, and real GZIP byte-savings comparisons.

100% Local Browser Engine · Zero Uploads2 Workspaces

JS (Terser AST), Safe CSS, HTML & SQL: Minify or beautify JavaScript via real Terser AST mangling, calc()-preserving CSS minification, HTML, and SQL with byte-delta metrics.

Input (JAVASCRIPT)
Processed Output
In: 446 B
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What is JS, CSS & HTML Code Studio?

Code Minifier & Formatter Studio minifies and beautifies JavaScript (via real Terser AST mangling and dead-code elimination), CSS, and HTML, and measures exact UTF-8 vs RFC 1952 GZIP wire transfer bytes with 3G/4G latency estimates.

How to use JS, CSS & HTML Code Studio in 3 steps
  1. 1

    Paste JS, CSS, or HTML source

    Choose Minify or Beautify, or switch to the Wire Size & GZIP Budget tab.

  2. 2

    Inspect syntax & byte savings

    Verify Terser AST compression and real browser CompressionStream('gzip') transfer weight.

  3. 3

    Copy or download

    Export production-ready .min.js, .min.css, or .min.html code.

Key features and benefits
  • Uses genuine Terser AST parsing for JavaScript rather than brittle regex stripping.
  • Measures real GZIP wire transfer bytes using native CompressionStream.
Common use cases

Checking how much a utility function adds to a frontend bundle after Terser + GZIP.

Minifying inline critical CSS and HTML email templates.

Why browser-based works better

JS, CSS & HTML Code Studio consolidates related developer & code studios workflows into one cohesive, multi-mode browser studio — eliminating tab-hopping across fragmented single-purpose tools.

Every mode executes locally using Web APIs and audited client-side libraries, so private files, tokens, and source code never leave your device.

You might also need

Continue this workflow with nearby browser-based tools so you can validate, convert, and ship output without context switching.

JS, CSS & HTML Code Studio FAQs

Quick answers about the workflow, privacy, and where this tool fits in a broader job.

Why measure GZIP size alongside minified size?

HTTP servers ship GZIP/Brotli streams; GZIP byte count reflects actual network transfer cost.

Related free tools

Keep the workflow moving with nearby tools that solve the next likely step.

Built and maintained by

Free AI Tools Engineering Team

Browser Tooling & Web Platform Engineering

Last updated:

Tested in Chrome, Firefox, and Safari on desktop and mobile.

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