JavaScript Formatter

Why this is different

Many browser beautifiers focus only on whitespace. This tool couples TypeScript’s production parser/formatter with OneFreePlace structural reflow, then reparses the result and compares the complete syntax-tree fingerprint and every comment payload before enabling Copy or Download.

• Auto-detects JS, JSX, TypeScript and TSX.
• Handles regex literals, template strings, optional chaining, decorators, generics and modern module syntax through the parser engine.
• Expands long collections, imports, calls and JSX attributes without source uploads.

Safety & limitations

Formatting is presentation work, not code transformation. The review audit only flags patterns such as eval, debugger, loose equality and TODO markers; it never changes them.

The bundled parser engine is TypeScript 5.8.3. Syntax newer than the engine can safely parse may be blocked rather than guessed.

For generated/minified vendor bundles, preserve-layout mode is usually safer than aggressive structural reflow. Always run your project’s own tests before deployment.

Useful workflow

1. Open a file or paste code.
2. Let Auto detect choose the parser, or select it explicitly.
3. Use Standard for normal work, Review for narrower reflow, Compact for fewer line breaks, or Preserve layout for whitespace-only cleanup.
4. Check Semantic guard and 2nd pass are both green before using the result.

Privacy

Formatting, parsing, diagnostics and ZIP creation happen in the browser. There is no upload endpoint in this package and no account requirement.