Phaser is an open source project and available to download for free. There are no fees to pay when using Phaser, regardless if you use it for a commercial or free project.
We use GitHub to manage the project and you have various options on how to download it. These are all explained on the download page. Please note that we recently released Phaser 3. This guide is for Phaser 2 and Phaser CE, so make sure you download a matching version for this guide.
Can I just get a zip/tar file?
Get Phaser by cloning the repository, grabbing the js file or downloading it all as a zip
Yes. GitHub provides the option to download the whole repository as a zip or tar file. However we would strongly recommend you learn to use git instead. It will allow you to easily update to the latest versions of Phaser as they are released. And if in time you wish to contribute code towards Phaser it makes doing so much easier.
If you don't fancy learning to use git via the command-line there are some great applications you can use instead. We'd recommend SmartGIT on Windows or Git Tower on OS X.