diff --git a/test/test_write_info_json.py b/test/test_write_info_json.py
index a5b6f6972..30c4859fd 100644
--- a/test/test_write_info_json.py
+++ b/test/test_write_info_json.py
@@ -31,7 +31,7 @@ params = get_params({
 
 
 TEST_ID = 'BaW_jenozKc'
-INFO_JSON_FILE = TEST_ID + '.mp4.info.json'
+INFO_JSON_FILE = TEST_ID + '.info.json'
 DESCRIPTION_FILE = TEST_ID + '.mp4.description'
 EXPECTED_DESCRIPTION = u'''test chars:  "'/\ä↭𝕐
 
diff --git a/youtube_dl/YoutubeDL.py b/youtube_dl/YoutubeDL.py
index bd093add8..a2e3df1f9 100644
--- a/youtube_dl/YoutubeDL.py
+++ b/youtube_dl/YoutubeDL.py
@@ -717,7 +717,7 @@ class YoutubeDL(object):
                     return
 
         if self.params.get('writeinfojson', False):
-            infofn = filename + u'.info.json'
+            infofn = os.path.splitext(filename)[0] + u'.info.json'
             self.report_writeinfojson(infofn)
             try:
                 json_info_dict = dict((k, v) for k, v in info_dict.items() if not k in ['urlhandle'])