What is the Closure Compiler?

The Closure Compiler is a tool for making JavaScript download and run faster. Instead of compiling from a source language to machine code, it compiles from JavaScript to better JavaScript. It parses your JavaScript, analyzes it, removes dead code and rewrites and minimizes what's left. It also checks syntax, variable references, and types, and warns about common JavaScript pitfalls.

How can I use the Closure Compiler?

You can use the Closure Compiler as:

An open source Java application that you can run from the command line.

A simple web application.

DEPRECATED A RESTful API.

To get started with the compiler, see "How do I start" below.

What are the benefits of using Closure Compiler?

• Efficiency. The Closure Compiler reduces the size of your JavaScript files and makes them more efficient, helping your application to load faster and reducing your bandwidth needs.

• Code checking. The Closure Compiler provides warnings for illegal JavaScript and warnings for potentially dangerous operations, helping you to produce JavaScript that is less buggy and easier to maintain.

  How do I start?

  • Work through the UI Hello World.
  • Work through the API Hello World.
  • Download the most recently released JAR file from the Maven repository.
  • Work through the Application Hello World.
  • Read about Advanced compilation.
  • Explore the project's source code.