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JavaScript Formatter

Format and beautify JavaScript code with consistent indentation and readable output.

Input

Output

JavaScript Formatter: complete usage guide

Format JavaScript snippets for readability and review clarity before debugging, code sharing, and production patching.

It rewrites JavaScript into consistent indentation and spacing for easier understanding.

It helps surface missing brackets or structural issues faster during local troubleshooting.

It reduces noisy diffs by aligning code style before review and merge workflows.

Compact code

const x=[1,2,3].map(n=>n*2);if(x.length){console.log(x)}

Async snippet

async function load(){const r=await fetch('/api');return r.json();}

Object sample

const cfg={retry:3,timeout:8000,headers:{'x-env':'prod'}};

Formatted code

const x = [1, 2, 3].map((n) => n * 2);

Readable async flow

async/await blocks split across lines for easier step-by-step debugging.

Review note

Run lint and tests after formatting to catch underlying logic issues.

Formatter output differs from project style

Align settings with repository lint/formatter configuration.

Syntax error prevents formatting

Fix malformed code first, then rerun formatter.

Assuming formatting fixed logic bug

Treat formatting as readability aid, not behavioral correction.

Mixed tabs and spaces create noisy diffs

Standardize indentation settings across tooling.

Start with a minimal input for JavaScript Formatter and verify baseline behavior first.
Make assumptions explicit: encoding, delimiter strategy, and timezone.
Change one variable at a time and compare output diffs.
Keep one verified output snapshot as a team reference.

Confirm JavaScript Formatter output is deterministic across repeated runs with identical input.
Check boundary inputs (empty values, long fields, invalid characters).
Remove sensitive data before sharing output externally.
Verify final rendering on both desktop and mobile viewports.