diff --git a/src/MutationTest.php b/src/MutationTest.php
index 062f524..de17e27 100644
--- a/src/MutationTest.php
+++ b/src/MutationTest.php
@@ -107,7 +107,7 @@ private function calculateTimeout(): int
             ->getInitialTestSuiteDuration()
             ->seconds();
 
-        return $initialTestSuiteDuration + max(5, $initialTestSuiteDuration * 1.2);
+        return $initialTestSuiteDuration + max(5, $initialTestSuiteDuration * 0.2);
     }
 
     public function hasFinished(): bool