diff --git a/tests/libtest/cli_ws_data.c b/tests/libtest/cli_ws_data.c
index 57c8cebb14..856d41ba1f 100644
--- a/tests/libtest/cli_ws_data.c
+++ b/tests/libtest/cli_ws_data.c
@@ -104,7 +104,7 @@ static CURLcode test_ws_data_m2_echo(const char *url,
   curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
   curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 2L); /* websocket style */
   result = curl_easy_perform(curl);
-  curl_mfprintf(stderr, "curl_easy_perform() returned %u\n", result);
+  curl_mfprintf(stderr, "curl_easy_perform() returned %d\n", result);
   if(result != CURLE_OK)
     goto out;
 
diff --git a/tests/libtest/cli_ws_pingpong.c b/tests/libtest/cli_ws_pingpong.c
index 5f932d1bcc..2ed12c8cab 100644
--- a/tests/libtest/cli_ws_pingpong.c
+++ b/tests/libtest/cli_ws_pingpong.c
@@ -78,7 +78,7 @@ static CURLcode test_cli_ws_pingpong(const char *URL)
     curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
     curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 2L); /* websocket style */
     result = curl_easy_perform(curl);
-    curl_mfprintf(stderr, "curl_easy_perform() returned %u\n", result);
+    curl_mfprintf(stderr, "curl_easy_perform() returned %d\n", result);
     if(result == CURLE_OK)
       result = pingpong(curl, payload);