diff --git a/src/Symfony/Component/Console/Terminal.php b/src/Symfony/Component/Console/Terminal.php
index 9189f2ded3574..ddef70d7bf0cc 100644
--- a/src/Symfony/Component/Console/Terminal.php
+++ b/src/Symfony/Component/Console/Terminal.php
@@ -31,7 +31,7 @@ public function getWidth()
             self::initDimensions();
         }
 
-        return self::$width;
+        return self::$width ?: 80;
     }
 
     /**
@@ -49,7 +49,7 @@ public function getHeight()
             self::initDimensions();
         }
 
-        return self::$height;
+        return self::$height ?: 50;
     }
 
     private static function initDimensions()