JavaScript minifier

Minify JavaScript with Terser: remove whitespace, shorten variables, and drop console calls. Supports ES modules and modern syntax.

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JavaScript

// Greets each user
function greetAll(users) {
  const greetings = [];
  for (const user of users) {
    const message = `Hello, ${user.name}!`;
    console.log(message);
    greetings.push(message);
  }
  return greetings;
}

greetAll([{ name: 'Ada' }, { name: 'Linus' }]);

Minified JavaScript

Shorten variable names Remove console.* calls ES module (import/export) Keep /*! license */ comments

How to use JavaScript minifier

Minify JavaScript with Terser, the same compressor used by most modern build tools.

Removes whitespace and comments, and shortens local variable names
Dead-code removal and constant folding, with two compression passes
Optionally drop console.* calls and keep license comments
Supports modern syntax and ES modules

Syntax errors are reported with the line and column.

JavaScript minifier FAQs

Is JavaScript minifier free?

JavaScript minifier is a free online tool on ReallyUseful.Tools. No account is required.

Does JavaScript minifier run in my browser?

JavaScript minifier is designed to run in your browser where supported, so files can stay on your device instead of being uploaded to a server.

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