Yii is an open source project released under the terms of the BSD License. This means that you can use Yii for free to develop either open-source or proprietary Web applications.
The latest version of Yii 2 is 2.0.6, released on August 10, 2015. Yii 2.0 is a complete rewrite of Yii on top of PHP 5.4.0. It is aimed to become a state-of-the-art of the new generation of PHP framework. Yii 2.0 is not compatible with 1.1.
There are two ways to install Yii 2: using Composer, or downloading an application template. We highly recommend you to use the former.
This is the preferred way of installing Yii 2.0. If you do not have Composer yet, you may install it by following the instructions here.
After installing Composer, run the following command to install the Composer Asset Plugin:
php composer.phar global require "fxp/composer-asset-plugin:~1.0.3"
Now choose one of the application templates to start installing Yii 2.0. An application template is a package that contains a skeleton Web application written in Yii.
php composer.phar create-project yiisoft/yii2-app-basic basic 2.0.6
php composer.phar create-project yiisoft/yii2-app-advanced advanced 2.0.6
Note that you may be prompted to enter your GitHub username and password during the installation process. This is normal. Just enter them and continue.
Download one of the following archive files, and then extract it to a Web-accessible folder:
If you are upgrading from Yii 2.0.0 with composer, simply run the following command in your project's root directory:
php composer.phar require yiisoft/yii2 2.0.6
If you installed Yii using an archive file, you should download the new release file, extract it and replace the older version with the new one.
Upgrading from Yii 1.1 is not trivial. Please refer to the guide about upgrading from Yii 1.1.
Yii 1.1 is currently under maintenance mode. Continued support and bug fixes for this version will be provided until December 31, 2015 or further if needed.
|Yii Framework 1.1.x|
|Latest Release||1.1.16 (Dec 21, 2014)|
change log, upgrade instructions
|Documentation||yii-docs-1.1.16.bca042.tar.gz (.zip file)|
|Requirement||PHP 5.1.0 or above|
|End of Maintenance||Dec 31, 2016|
|Security support until||Dec 31, 2018 (may be extended further if needed)|
|Release History||download archived releases|
You can obtain the latest development version of Yii from GitHub repository using the following URL:
You can also obtain the latest Yii source code via SVN using:
svn checkout https://github.com/yiisoft/yii/trunk/ yii