JavaScript Formatter – Validation and Formatting Hub

Make ESM, CommonJS, and framework code blocks consistent, readable, and aligned with team guidelines in seconds.

Input

Formatted Output

Formatting Options

Line width

Indent width

Use tabsEnable

Use semicolonsEnable

Use single quotesEnable

Trailing commas

Examples

Minified JS

const x=[1,2,3].map(n=>n*2);function f(a){return{a}}

Long lines

const message = "Hello" + " ".repeat(3) + "World!"; export const fn=(a,b,c)=>({a,b,c})

How does the JavaScript Formatter work?

Prettier parses your source into an AST, then applies the formatting profile you select. Conditional blocks, arrow functions, import/export statements, and object literals get predictable spacing.

Only the necessary Prettier plugins are loaded, so even large codebases respond quickly. When parsing fails, the offending line is highlighted with a descriptive message.

What is JavaScript?

JavaScript is the dynamic language powering interactive web experiences in browsers and on servers through Node.js. Modern ecosystems introduce modules, async flows, and component patterns that inflate code volume.

Consistent formatting keeps that growing surface area maintainable, shortens reviews, and lowers the barrier for new contributors joining the team.

Best practices and scenarios

Wire the formatter into pre-commit hooks or continuous integration to guarantee style compliance across monorepos and micro-frontends.

Before you publish tutorials or onboarding guides, run snippets through the tool so examples shine regardless of framework choice.

Frequently Asked Questions

Does the tool support JSX or TSX?

This formatter targets pure JavaScript. For React or TypeScript projects, switch to the dedicated JSX or TypeScript formatters to retain language-specific semantics.

How should I choose a trailing comma setting?

`es5` works for most repositories. Choose `all` when immutability or multiline argument lists dominate so diffs stay small, or `none` if your linter disallows commas.

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JavaScript Formatter – Modern Code Style Companion

Make ESM, CommonJS, and framework code blocks consistent, readable, and aligned with team guidelines in seconds.

The JavaScript Formatter relies on Prettier's Babel and ESTree plugins to refresh even complex code. Optional chaining, async functions, dynamic imports, and JSX-like syntax are reformatted without altering behavior. Choose line width, tab width, semicolons, quote style, and trailing comma strategy to match your repository rules. Clear error messages surface syntax issues long before they break builds, while SEO-friendly content keeps the tool discoverable for future teammates.

Keywords

#javascript formatter#format javascript#js beautifier#prettier javascript#code style tool#javascript pretty print

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JavaScript Formatter – Modern Code Style Companion