diff --git a/src/calibre/gui2/convert/bulk.py b/src/calibre/gui2/convert/bulk.py
index abb66c1fd8..5324a83865 100644
--- a/src/calibre/gui2/convert/bulk.py
+++ b/src/calibre/gui2/convert/bulk.py
@@ -126,7 +126,8 @@ class BulkConfig(Config):
     def setup_output_formats(self, db, preferred_output_format):
         if preferred_output_format:
             preferred_output_format = preferred_output_format.lower()
-        output_formats = sorted(available_output_formats())
+        output_formats = sorted(available_output_formats(),
+                key=lambda x:{'EPUB':'!A', 'MOBI':'!B'}.get(x.upper(), x))
         output_formats.remove('oeb')
         preferred_output_format = preferred_output_format if \
             preferred_output_format and preferred_output_format \
diff --git a/src/calibre/gui2/convert/single.py b/src/calibre/gui2/convert/single.py
index c889df71fd..9160c820bd 100644
--- a/src/calibre/gui2/convert/single.py
+++ b/src/calibre/gui2/convert/single.py
@@ -242,7 +242,8 @@ class Config(ResizableDialog, Ui_Dialog):
             preferred_output_format):
         if preferred_output_format:
             preferred_output_format = preferred_output_format.lower()
-        output_formats = sorted(available_output_formats())
+        output_formats = sorted(available_output_formats(),
+                key=lambda x:{'EPUB':'!A', 'MOBI':'!B'}.get(x.upper(), x))
         output_formats.remove('oeb')
         input_format, input_formats = get_input_format_for_book(db, book_id,
                 preferred_input_format)