diff --git a/bin/phpstan b/bin/phpstan
index 537f3e123d..a8c0fd8dd0 100755
--- a/bin/phpstan
+++ b/bin/phpstan
@@ -3,6 +3,7 @@
 
 use PHPStan\Command\AnalyseCommand;
 use PHPStan\Command\ClearResultCacheCommand;
+use PHPStan\Command\DiagnoseCommand;
 use PHPStan\Command\DumpParametersCommand;
 use PHPStan\Command\FixerWorkerCommand;
 use PHPStan\Command\WorkerCommand;
@@ -166,5 +167,6 @@ use Symfony\Component\Console\Helper\ProgressBar;
 	$application->add(new ClearResultCacheCommand($reversedComposerAutoloaderProjectPaths));
 	$application->add(new FixerWorkerCommand($reversedComposerAutoloaderProjectPaths));
 	$application->add(new DumpParametersCommand($reversedComposerAutoloaderProjectPaths));
+	$application->add(new DiagnoseCommand($reversedComposerAutoloaderProjectPaths));
 	$application->run();
 })();
diff --git a/src/Command/DiagnoseCommand.php b/src/Command/DiagnoseCommand.php
new file mode 100644
index 0000000000..608cf732f1
--- /dev/null
+++ b/src/Command/DiagnoseCommand.php
@@ -0,0 +1,104 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Command;
+
+use PHPStan\Diagnose\DiagnoseExtension;
+use PHPStan\Diagnose\PHPStanDiagnoseExtension;
+use PHPStan\ShouldNotHappenException;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+use function is_string;
+
+class DiagnoseCommand extends Command
+{
+
+	private const NAME = 'diagnose';
+
+	/**
+	 * @param string[] $composerAutoloaderProjectPaths
+	 */
+	public function __construct(
+		private array $composerAutoloaderProjectPaths,
+	)
+	{
+		parent::__construct();
+	}
+
+	protected function configure(): void
+	{
+		$this->setName(self::NAME)
+			->setDescription('Shows diagnose information about PHPStan and extensions')
+			->setDefinition([
+				new InputOption('configuration', 'c', InputOption::VALUE_REQUIRED, 'Path to project configuration file'),
+				new InputOption(AnalyseCommand::OPTION_LEVEL, 'l', InputOption::VALUE_REQUIRED, 'Level of rule options - the higher the stricter'),
+				new InputOption('autoload-file', 'a', InputOption::VALUE_REQUIRED, 'Project\'s additional autoload file path'),
+				new InputOption('debug', null, InputOption::VALUE_NONE, 'Show debug information - do not catch internal errors'),
+				new InputOption('memory-limit', null, InputOption::VALUE_REQUIRED, 'Memory limit for clearing result cache'),
+			]);
+	}
+
+	protected function initialize(InputInterface $input, OutputInterface $output): void
+	{
+		if ((bool) $input->getOption('debug')) {
+			$application = $this->getApplication();
+			if ($application === null) {
+				throw new ShouldNotHappenException();
+			}
+			$application->setCatchExceptions(false);
+			return;
+		}
+	}
+
+	protected function execute(InputInterface $input, OutputInterface $output): int
+	{
+		$memoryLimit = $input->getOption('memory-limit');
+		$autoloadFile = $input->getOption('autoload-file');
+		$configuration = $input->getOption('configuration');
+		$level = $input->getOption(AnalyseCommand::OPTION_LEVEL);
+
+		if (
+			(!is_string($memoryLimit) && $memoryLimit !== null)
+			|| (!is_string($autoloadFile) && $autoloadFile !== null)
+			|| (!is_string($configuration) && $configuration !== null)
+			|| (!is_string($level) && $level !== null)
+		) {
+			throw new ShouldNotHappenException();
+		}
+
+		try {
+			$inceptionResult = CommandHelper::begin(
+				$input,
+				$output,
+				[],
+				$memoryLimit,
+				$autoloadFile,
+				$this->composerAutoloaderProjectPaths,
+				$configuration,
+				null,
+				$level,
+				false,
+			);
+		} catch (InceptionNotSuccessfulException) {
+			return 1;
+		}
+
+		$container = $inceptionResult->getContainer();
+		$output = $inceptionResult->getStdOutput();
+
+		/** @var PHPStanDiagnoseExtension $phpstanDiagnoseExtension */
+		$phpstanDiagnoseExtension = $container->getService('phpstanDiagnoseExtension');
+
+		// not using tag for this extension to make sure it's always first
+		$phpstanDiagnoseExtension->print($output);
+
+		/** @var DiagnoseExtension $extension */
+		foreach ($container->getServicesByTag(DiagnoseExtension::EXTENSION_TAG) as $extension) {
+			$extension->print($output);
+		}
+
+		return 0;
+	}
+
+}
diff --git a/src/Diagnose/DiagnoseExtension.php b/src/Diagnose/DiagnoseExtension.php
index 5df5d628ef..084134495a 100644
--- a/src/Diagnose/DiagnoseExtension.php
+++ b/src/Diagnose/DiagnoseExtension.php
@@ -26,6 +26,6 @@ interface DiagnoseExtension
 
 	public const EXTENSION_TAG = 'phpstan.diagnoseExtension';
 
-	public function print(Output $errorOutput): void;
+	public function print(Output $output): void;
 
 }
diff --git a/src/Diagnose/PHPStanDiagnoseExtension.php b/src/Diagnose/PHPStanDiagnoseExtension.php
index 9184987cb8..a7eb786ed8 100644
--- a/src/Diagnose/PHPStanDiagnoseExtension.php
+++ b/src/Diagnose/PHPStanDiagnoseExtension.php
@@ -15,23 +15,23 @@ public function __construct(private PhpVersion $phpVersion)
 	{
 	}
 
-	public function print(Output $errorOutput): void
+	public function print(Output $output): void
 	{
 		$phpRuntimeVersion = new PhpVersion(PHP_VERSION_ID);
-		$errorOutput->writeLineFormatted(sprintf(
+		$output->writeLineFormatted(sprintf(
 			'<info>PHP runtime version:</info> %s',
 			$phpRuntimeVersion->getVersionString(),
 		));
-		$errorOutput->writeLineFormatted(sprintf(
+		$output->writeLineFormatted(sprintf(
 			'<info>PHP version for analysis:</info> %s (from %s)',
 			$this->phpVersion->getVersionString(),
 			$this->phpVersion->getSourceLabel(),
 		));
-		$errorOutput->writeLineFormatted(sprintf(
+		$output->writeLineFormatted(sprintf(
 			'<info>PHPStan version:</info> %s',
 			ComposerHelper::getPhpStanVersion(),
 		));
-		$errorOutput->writeLineFormatted('');
+		$output->writeLineFormatted('');
 	}
 
 }