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NeatUtility

JavaScript Formatter & Minifier

Code Formatters100% Client-Side
Ready
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0 B / 4.77 MB
About this tool, examples & FAQ

Format messy JavaScript into clean, readable code with configurable indentation and semicolon style, or minify code locally without sending scripts to external servers.

Key facts

Verified capabilities and limits of this utility
Formatter EnginePrettier Babel parser in an isolated Web Worker
Supported OperationsBeautify (format) and Minify
Privacy & Security100% Client-side execution; code is never uploaded
Maximum Input5 MB

How to use

  1. Paste your JavaScript function, module, or snippet into the input editor.
  2. Choose your desired indentation size, tab settings, semicolon preference, and quote style.
  3. Click 'Format JS' to beautify the code or select 'Minify JS' to strip comments and trailing whitespace.
  4. Copy or download the formatted script for your project.

Examples

Format Function Declaration

Input

function test(a,b){return a+b;}

Example output

function test(a, b) {
  return a + b;
}

Minify JavaScript Code

Input

// Calculates sum
function add(x, y) {
  /* Return sum */
  return x + y;
}

Example output

function add(x, y) {
return x + y;
}

Edge cases

Automatic Semicolon Insertion (ASI)

When semicolons are disabled in options, Prettier only omits semicolons where safe under ECMAScript ASI rules, preventing syntax errors in return or destructuring statements.

Async/Await and Top-level Await

Modern ES2024+ syntax including async generators, private class fields, optional chaining, and nullish coalescing operators format reliably.

JSX and TypeScript Syntax

Standard JavaScript with ES module syntax is supported. For specialized JSX or strict TypeScript type annotations, use the dedicated JSX Formatter and TypeScript Formatter tools.

How it works

  1. Tokenizes and parses JavaScript using Prettier's Babel parser inside a client-side Web Worker.
  2. Applies consistent line breaks, argument alignment, indentation, and operator spacing.
  3. Minification removes single-line comments, block comments, and blank lines to reduce file footprint.
  4. Returns the formatted code directly to your browser pane without transmitting data over the network.

Related workflows

Frequently asked questions

Is my JavaScript code uploaded to any server?

No. All parsing and formatting takes place entirely in your browser using an isolated Web Worker.

Which ECMAScript version does this formatter support?

The formatter supports ECMAScript 2024 and modern stage 3/4 proposals including private fields, decorators, and pattern matching syntax.

Can I format code with or without semicolons?

Yes. Use the Semicolons option toggle to choose between StandardJS-style semicolon-free code or standard semicolon-terminated statements.

References