diff --git a/CHANGELOG.md b/CHANGELOG.md
index c5cebbf3..e79b3c2f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 ## 3.6.0 (xxxx-xx-xx)
 
-* Add support for Symfony Mailer
+* Added support for Symfony Mailer
+* Added support for setting log levels from parameters or environment variables
 
 ## 3.5.0 (2019-11-13)
 
diff --git a/DependencyInjection/MonologExtension.php b/DependencyInjection/MonologExtension.php
index 5a7177ec..3e24d1fd 100644
--- a/DependencyInjection/MonologExtension.php
+++ b/DependencyInjection/MonologExtension.php
@@ -23,6 +23,7 @@
 use Symfony\Component\DependencyInjection\Argument\BoundArgument;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Definition;
+use Symfony\Component\DependencyInjection\Exception\ParameterNotFoundException;
 use Symfony\Component\DependencyInjection\Loader\XmlFileLoader;
 use Symfony\Component\DependencyInjection\Reference;
 use Symfony\Component\HttpKernel\DependencyInjection\Extension;
@@ -41,9 +42,31 @@ class MonologExtension extends Extension
 
     private $swiftMailerHandlers = [];
 
-    private function levelToMonologConst($level)
+    private function levelToMonologConst($level, ContainerBuilder $container)
     {
-        return is_int($level) ? $level : constant('Monolog\Logger::'.strtoupper($level));
+        if (null === $level || is_numeric($level)) {
+            return $level;
+        }
+
+        if (defined('Monolog\Logger::'.strtoupper($level))) {
+            return constant('Monolog\Logger::' . strtoupper($level));
+        }
+
+        if ($container->hasParameter($level)) {
+            return $this->levelToMonologConst($container->getParameter($level), $container);
+        }
+
+        try {
+            $logLevel = $container->resolveEnvPlaceholders($level, true);
+        } catch (ParameterNotFoundException $notFoundException) {
+            throw new \InvalidArgumentException(sprintf('Could not match "%s" to a log level.', $level));
+        }
+
+        if ($logLevel !== '') {
+            return $this->levelToMonologConst($logLevel, $container);
+        }
+
+        throw new \InvalidArgumentException(sprintf('Could not match "%s" to a log level.', $level));
     }
 
     /**
@@ -169,7 +192,7 @@ private function buildHandler(ContainerBuilder $container, $name, array $handler
         $handlerClass = $this->getHandlerClassByType($handler['type']);
         $definition = new Definition($handlerClass);
 
-        $handler['level'] = $this->levelToMonologConst($handler['level']);
+        $handler['level'] = $this->levelToMonologConst($handler['level'], $container);
 
         if ($handler['include_stacktraces']) {
             $definition->setConfigurator(['Symfony\\Bundle\\MonologBundle\\MonologBundle', 'includeStacktraces']);
@@ -383,9 +406,9 @@ private function buildHandler(ContainerBuilder $container, $name, array $handler
             break;
 
         case 'fingers_crossed':
-            $handler['action_level'] = $this->levelToMonologConst($handler['action_level']);
+            $handler['action_level'] = $this->levelToMonologConst($handler['action_level'], $container);
             if (null !== $handler['passthru_level']) {
-                $handler['passthru_level'] = $this->levelToMonologConst($handler['passthru_level']);
+                $handler['passthru_level'] = $this->levelToMonologConst($handler['passthru_level'], $container);
             }
             $nestedHandlerId = $this->getHandlerId($handler['handler']);
             $this->markNestedHandler($nestedHandlerId);
@@ -429,10 +452,10 @@ private function buildHandler(ContainerBuilder $container, $name, array $handler
             break;
 
         case 'filter':
-            $handler['min_level'] = $this->levelToMonologConst($handler['min_level']);
-            $handler['max_level'] = $this->levelToMonologConst($handler['max_level']);
+            $handler['min_level'] = $this->levelToMonologConst($handler['min_level'], $container);
+            $handler['max_level'] = $this->levelToMonologConst($handler['max_level'], $container);
             foreach (array_keys($handler['accepted_levels']) as $k) {
-                $handler['accepted_levels'][$k] = $this->levelToMonologConst($handler['accepted_levels'][$k]);
+                $handler['accepted_levels'][$k] = $this->levelToMonologConst($handler['accepted_levels'][$k], $container);
             }
 
             $nestedHandlerId = $this->getHandlerId($handler['handler']);
diff --git a/Tests/DependencyInjection/MonologExtensionTest.php b/Tests/DependencyInjection/MonologExtensionTest.php
index 732d4cd6..d3742027 100644
--- a/Tests/DependencyInjection/MonologExtensionTest.php
+++ b/Tests/DependencyInjection/MonologExtensionTest.php
@@ -18,6 +18,7 @@
 use Symfony\Bundle\MonologBundle\DependencyInjection\Compiler\LoggerChannelPass;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Definition;
+use Symfony\Component\DependencyInjection\ParameterBag\EnvPlaceholderParameterBag;
 use Symfony\Component\DependencyInjection\Reference;
 use Symfony\Component\Config\Definition\Exception\InvalidConfigurationException;
 use Symfony\Component\HttpFoundation\RequestStack;
@@ -611,10 +612,94 @@ public function v1AddedDataProvider()
         ];
     }
 
+    public function testLogLevelfromInvalidparameterThrowsException()
+    {
+        $container = new ContainerBuilder();
+        $loader = new MonologExtension();
+        $config = [['handlers' => ['main' => ['type' => 'stream', 'level' => '%some_param%']]]];
 
-    protected function getContainer(array $config = [], array $thirdPartyDefinitions = [])
+        $this->expectException(InvalidArgumentException::class);
+        $this->expectExceptionMessage('Could not match "%some_param%" to a log level.');
+
+        $loader->load($config, $container);
+    }
+
+    /**
+     * @dataProvider provideLoglevelParameterConfig
+     */
+    public function testLogLevelfromParameter(array $parameters, array $config, $expectedClass, array $expectedArgs)
     {
         $container = new ContainerBuilder();
+        foreach ($parameters as $name => $value) {
+            $container->setParameter($name, $value);
+        }
+        $loader = new MonologExtension();
+        $config = [['handlers' => ['main' => $config]]];
+        $loader->load($config, $container);
+
+        $definition = $container->getDefinition('monolog.handler.main');
+        $this->assertDICDefinitionClass($definition, $expectedClass);
+        $this->assertDICConstructorArguments($definition, $expectedArgs);
+    }
+
+    public function provideLoglevelParameterConfig()
+    {
+        return [
+            'browser console with parameter level' => [
+                ['%log_level%' => 'info'],
+                ['type' => 'browser_console', 'level' => '%log_level%'],
+                'Monolog\Handler\BrowserConsoleHandler',
+                [200, true]
+            ],
+            'browser console with envvar level' => [
+                ['%env(LOG_LEVEL)%' => 'info'],
+                ['type' => 'browser_console', 'level' => '%env(LOG_LEVEL)%'],
+                'Monolog\Handler\BrowserConsoleHandler',
+                [200, true]
+            ],
+            'stream with envvar level null or "~" (in yaml config)' => [
+                ['%env(LOG_LEVEL)%' => null],
+                ['type' => 'stream', 'level' => '%env(LOG_LEVEL)%'],
+                'Monolog\Handler\StreamHandler',
+                [
+                    '%kernel.logs_dir%/%kernel.environment%.log',
+                    null,
+                    true,
+                    null,
+                    false,
+                ]
+            ],
+            'stream with envvar level' => [
+                ['%env(LOG_LEVEL)%' => '400'],
+                ['type' => 'stream', 'level' => '%env(LOG_LEVEL)%'],
+                'Monolog\Handler\StreamHandler',
+                [
+                    '%kernel.logs_dir%/%kernel.environment%.log',
+                    400,
+                    true,
+                    null,
+                    false,
+                ]
+            ],
+            'stream with envvar and fallback parameter' => [
+                ['%env(LOG_LEVEL)%' => '500', '%log_level%' => '%env(LOG_LEVEL)%'],
+                ['type' => 'stream', 'level' => '%log_level%'],
+                'Monolog\Handler\StreamHandler',
+                [
+                    '%kernel.logs_dir%/%kernel.environment%.log',
+                    500,
+                    true,
+                    null,
+                    false,
+                ]
+            ],
+        ];
+    }
+
+
+    protected function getContainer(array $config = [], array $thirdPartyDefinitions = [])
+    {
+        $container = new ContainerBuilder(new EnvPlaceholderParameterBag());
         foreach ($thirdPartyDefinitions as $id => $definition) {
             $container->setDefinition($id, $definition);
         }