diff --git a/python/dune/perftool/sumfact/vectorization.py b/python/dune/perftool/sumfact/vectorization.py
index 3635b5b26bd6f6df08e952d435ed52f304695587..14b9ba4de00eb1e7730ae3daf107ce9e6a762631 100644
--- a/python/dune/perftool/sumfact/vectorization.py
+++ b/python/dune/perftool/sumfact/vectorization.py
@@ -271,7 +271,7 @@ def level1_optimal_vectorization_strategy(sumfacts, width):
         print("The score in 'target' logic was: {}".format(strategy_cost((qp, optimal_strategies[qp]))))
 
         # Print the employed vectorization strategy into a file
-        filename = "targetstrat_{}.txt".format(int(float(get_form_option("vectorization_target"))))
+        filename = "targetstrat_{}.log".format(int(float(get_form_option("vectorization_target"))))
         with open(filename, 'w') as f:
             f.write("\n".join(stringify_vectorization_strategy((qp, optimal_strategies[qp]))))