Free Online JavaScript Formatter

A JavaScript formatter applies brace-aware indentation to a JS file — every `{` increases the indent, every `}` decreases it, and statements break on semicolons.

Your data is processed entirely in your browser and never sent to any server.

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Lightweight brace-aware beautifier. For production code, run Prettier or ESLint in your build.

How to Use This Developer Tool

  1. Paste your JavaScript into the input area.
  2. Pick an indent size (2 or 4 spaces).
  3. Read the formatted output in the right panel.
  4. Click Copy to send the result to your clipboard.

What Is a JavaScript Formatter?

When you grab a script off a CDN, a minified bundle from network inspector, or a one-liner from a Stack Overflow answer, a brace-aware formatter is usually enough to make sense of the structure: nested blocks indent, functions and loops surface, and you can read what's actually happening.

This is not a Prettier replacement. It doesn't reflow long lines, normalise quote style, or deeply understand JSX and template literals. For codebases, set up Prettier or ESLint with formatting rules in your build. For one-off inspection of a script you can't run through a real toolchain, this is faster.

Frequently Asked Questions

What does a JavaScript formatter do?
A JS formatter adds consistent indentation, line breaks, and spacing to minified or messy code. It makes code readable without changing behavior.
Is this a full Prettier replacement?
No — this is a lightweight in-browser beautifier. For production code, run Prettier or ESLint as part of your build.
Can I format TypeScript?
Most TypeScript code formats reasonably well as JavaScript. Type-specific syntax should remain intact.

Published by the WeGotEveryTool team. We build and test every tool in-house and update pages when the underlying spec, formula, or recommendation changes.

Reviewed: May 2026. Disclaimer: this tool is provided as-is for general informational use. For decisions with material consequences (medical, legal, financial, security) verify results against a qualified professional source.

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