diff --git a/speedtest_cli.py b/speedtest_cli.py
index 452c3fa..10e0889 100755
--- a/speedtest_cli.py
+++ b/speedtest_cli.py
@@ -487,7 +487,7 @@ def speedtest():
     except AttributeError:
         pass
     parser.add_argument('--bytes', dest='units', action='store_const',
-                        const=('bytes', 1), default=('bits', 8),
+                        const=('byte', 1), default=('bit', 8),
                         help='Display values in bytes instead of bits. Does '
                              'not affect the image generated by --share')
     parser.add_argument('--share', action='store_true',