diff --git a/etc/ci/performance/test_all.sh b/etc/ci/performance/test_all.sh
index c112a20c8b3..77fce655e8a 100755
--- a/etc/ci/performance/test_all.sh
+++ b/etc/ci/performance/test_all.sh
@@ -49,7 +49,7 @@ python3 -m http.server > /dev/null 2>&1 &
 # MANIFEST="page_load_test/tp5n/20160509.manifest" # A manifest that excludes
 MANIFEST="page_load_test/example.manifest" # A manifest that excludes
                                                  # timeout test cases
-PERF_FILE="output/perf-$(date +%s).json"
+PERF_FILE="output/perf-$(date +%s).csv"
 
 echo "Running tests"
 python3 runner.py ${engine} --runs 4 --timeout "${timeout}" --base "${base}" \