diff --git a/scrapy/commands/crawl.py b/scrapy/commands/crawl.py
index 53d2137dc..2fd102cc3 100644
--- a/scrapy/commands/crawl.py
+++ b/scrapy/commands/crawl.py
@@ -19,8 +19,8 @@ class Command(ScrapyCommand):
                           help="set spider argument (may be repeated)")
         parser.add_option("-o", "--output", metavar="FILE",
                           help="dump scraped items into FILE (use - for stdout)")
-        parser.add_option("-t", "--output-format", metavar="FORMAT", default="jsonlines",
-                          help="format to use for dumping items with -o (default: %default)")
+        parser.add_option("-t", "--output-format", metavar="FORMAT",
+                          help="format to use for dumping items with -o")
 
     def process_options(self, args, opts):
         ScrapyCommand.process_options(self, args, opts)
diff --git a/scrapy/commands/runspider.py b/scrapy/commands/runspider.py
index 414f4c43f..a9b429ec4 100644
--- a/scrapy/commands/runspider.py
+++ b/scrapy/commands/runspider.py
@@ -41,8 +41,8 @@ class Command(ScrapyCommand):
                           help="set spider argument (may be repeated)")
         parser.add_option("-o", "--output", metavar="FILE",
                           help="dump scraped items into FILE (use - for stdout)")
-        parser.add_option("-t", "--output-format", metavar="FORMAT", default="jsonlines",
-                          help="format to use for dumping items with -o (default: %default)")
+        parser.add_option("-t", "--output-format", metavar="FORMAT",
+                          help="format to use for dumping items with -o")
 
     def process_options(self, args, opts):
         ScrapyCommand.process_options(self, args, opts)