Xdebug — Step Debugger and Debugging Aid for PHP
2938 461 125 0


Xdebug is a debugging tool for PHP. It provides step-debugging and a whole range of development helpers, such as stack traces, a code profiler, features to dump the full execution of your script to a file, and more.

Repography logo / Recent activity Time period

Timeline graphPull request status graphTrending topicsTop contributors


Xdebug requires a supported version of PHP. For installation it requires the `pecl` tool (available through the `php-pear` package), unless your Linux distribution has an Xdebug package (`php-xdebug`).


On most Linux distributions you can install Xdebug through its package manager. You can also compile from source with the `pecl` tool through `pecl install xdebug`. The latter also works for MacOS as long as PHP is installed with Homebrew.

On Windows, you need to download a binary. Use the Wizard.

Unless you have installed Xdebug with a package manager on Linux, you also need to add the following line to your `php.ini` file, or create a new Xdebug specific ini file `xdebug.ini` in the `conf.d` directory. In either case, it needs the following line added:


For more extensive installation instructions, see the documentation at


Most features in Xdebug have to be opted in into. Each feature has a specific opt-in. For example to use the step debugger you need to set xdebug.remote_enable=1` in your configuration file. The step debugger requires an IDE (client), of which there are many `available.

The documentation has instructions for each of Xdebug's features: and a full list of settings is also available there.


Xdebug is written in C, and extensive knowledge of PHP's internals is necessary to be able to contribute. Contributing guidance is available separately.

Before you begin to contribute, please reach out first. Either through email (address at the bottom), an issue in the issue tracker or preferably through IRC on Freenode's #xdebug channel.


If you are familiar with compiling PHP extension from source, have a local checkout of Xdebug's GitHub repository, and have compiled Xdebug in that directory following the instructions under installation you can run Xdebug's tests by running:

php run-xdebug-tests.php

The test framework requires that the PHP binary on the path has Xdebug loaded, with remote debugging enabled through `xdebug.mode=debug`. It is possible to skip remote debugging tests by exporting the `SKIP_DBGP_TESTS=1` environment variable.

The `SKIP_UNPARALLEL_TESTS=1` can be used to skip tests that can not run in parallel environments, and the `SKIP_SLOW_TESTS=1` environment variable to skip slow tests. The `OPCACHE` environment variable can either be `yes` or `no` and controls whether the test framework enables or disables OpCache.


Xdebug is released under The Xdebug License, which is based on The PHP License. It is an Open Source license (though not explicitly endorsed by the Open Source Initiative).

Further Reading

Xdebug has extensive documentation on its website. There are over a hundred settings and many functions documented. Please have a look through the wealth of information that Xdebug can provide to make your every day development with PHP easier.


For questions regarding Xdebug, please use StackOverflow, and tag your question with `xdebug`.

You can also find ad-hoc and sporadic support on IRC: freenode/#xdebug. You can do that with your favourite client, or by using their webchat.

If you think that you encountered a bug, please file a detailed bug report at You are required to create an account, this is so that you can be contacted for additional information and to keep out spam.

Derick Rethans — [email protected]