JavaScript Formatter

How to use JavaScript Formatter

1. Open JavaScript Formatter — it runs entirely in your browser with no setup.
2. Paste or type your input into the text area, or upload a file where supported.
3. Set any options you need. The result appears in the output panel — there is no upload step and no waiting on a server.
4. Review the output instantly; large inputs are handled locally without lag.
5. Copy the result to your clipboard or download it. Your data never leaves the page.

Why use JavaScript Formatter?

• 100% free with no limits, no sign-up and no watermarks.
• Private by design — your data are processed in your browser and never uploaded to a server.
• Fast and lightweight, with instant results even on a phone or a slow connection.
• Works everywhere — any modern browser on Windows, macOS, Linux, Android or iOS.
• Part of a full developer tools suite, so related javascript formatter tasks are one click away.

What people use JavaScript Formatter for

• Making a minified or badly indented script readable before debugging it.
• Normalising formatting across a snippet copied from several sources.
• Inspecting third-party code that ships without a source map.

JavaScript Formatter: limits and things worth knowing

• Formatting changes only whitespace and line breaks, never behaviour — with one edge case: code that relies on automatic semicolon insertion can change meaning when lines are rejoined. Well-formed code with explicit semicolons is unaffected.
• A formatter is not a linter. It will not tell you about unused variables, shadowed names or likely bugs; it only makes the structure visible.
• Beautifying minified code recovers the structure but not the names. Variables mangled to a, b, c stay that way, because the original names are gone from the file.

Is it private and secure?

Your privacy is built in. JavaScript Formatter runs completely on your device, so whatever you enter stays in your browser and is never transmitted, logged or stored on any server.

Network activity: none. Nothing is sent and nothing is fetched. This tool makes no network request at all once the page has loaded — which is why it keeps working if your connection drops.

You do not have to take that on trust — our privacy proof page publishes the Content-Security-Policy that enforces it, lists every third party it permits, and shows how to verify the whole claim yourself.

Learn more

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