Displays a debug bar in the browser with information from php. No more var_dump() in your code!

Note: Debug Bar is for development use only. Never install this on websites that are publicly accessible.

Debugbar has had significant updates in 3.x (January 2026). See the Release Notes for more information and breaking changes.

Features:

• Generic Debug Bar for PHP projects
• Easy to integrate with any project
• Clean, fast and easy to use interface
• Handles AJAX request
• Includes generic data collectors and collectors for well known libraries
• The client side bar is 100% coded in plain javascript
• Easily create your own collectors and their associated view in the bar
• Save and re-open previous requests
• Very well documented

Includes collectors for:

• Messages
• Config
• Time
• Memory
• Exceptions
• PHP Info
• Request Data
• Templates
• Object Count
• PDO
• Monolog
• Symfony Mailer
• Symfony HttpFoundation

Checkout the demo for examples and php-debugbar.com for a live example.

Additional collectors are available here:

• Twig
• Doctrine
• Monolog
• Symfony

Integrations with other frameworks:

• Laravel
• Zend Framework 2
• Phalcon
• SilverStripe
• Grav CMS
• TYPO3
• Joomla
• Drupal
• October CMS
• Winter CMS
• ZubZet Framework (From v1.2.0+)
• Framework-agnostic middleware and PSR-7 with php-middleware/phpdebugbar
• Dotkernel Frontend Application

(drop me a message or submit a PR to add your DebugBar related project here)

The best way to install DebugBar is using Composer with the following command:

composer require --dev php-debugbar/php-debugbar

DebugBar is very easy to use and you can add it to any of your projects in no time. The easiest way is using the render() functions

<?php

// Require the Composer autoloader, if not already loaded
require 'vendor/autoload.php';

use DebugBar\StandardDebugBar;

$debugbar = new StandardDebugBar();
$debugbarRenderer = $debugbar->getJavascriptRenderer();

$debugbar["messages"]->addMessage("hello world!");
?>
<html>
    <head>
        <?php echo $debugbarRenderer->renderHead() ?>
    </head>
    <body>
        ...
        <?php echo $debugbarRenderer->render() ?>
    </body>
</html>

The DebugBar uses DataCollectors to collect data from your PHP code. Some of them are automated but others are manual. Use the DebugBar like an array where keys are the collector names. In our previous example, we add a message to the MessagesCollector:

$debugbar["messages"]->addMessage("hello world!");

StandardDebugBar activates the following collectors:

• MemoryCollector (memory)
• MessagesCollector (messages)
• PhpInfoCollector (php)
• RequestDataCollector (request)
• TimeDataCollector (time)
• ExceptionsCollector (exceptions)

Learn more about DebugBar in the docs.

To run the demo, clone this repository and start the Built-In PHP webserver from the demo folder:

composer run demo

Then visit http://localhost:8000/

To test, run php vendor/bin/phpunit. To debug Browser tests, you can run PANTHER_NO_HEADLESS=1 vendor/bin/phpunit --debug. Run vendor/bin/bdi detect drivers to download the latest drivers.

When contributing to the JavaScript codebase:

1. Run npm run lint and npm run build before committing
2. Fix any errors (warnings are acceptable but should be minimized)
3. Use npm run lint:fix for automatic fixes where possible
4. Follow the ES6+ patterns established in the codebase

When contributing to the PHP codebase:

1. Run composer check-style and composer analyse before committing.
2. Make sure the tests pass (see above)
3. Verify that the demo works correctly (php -S localhost:8000 demo/)