diff --git a/src/calibre/gui2/actions/catalog.py b/src/calibre/gui2/actions/catalog.py
index fadb140be6..2af02efd13 100644
--- a/src/calibre/gui2/actions/catalog.py
+++ b/src/calibre/gui2/actions/catalog.py
@@ -31,10 +31,10 @@ class GenerateCatalogAction(InterfaceAction):
                     _('No books selected for catalog generation'),
                     show=True)
 
-		db = self.gui.library_view.model().db
-		dbspec = {}
-		for id in ids:
-			dbspec[id] = {'ondevice': db.ondevice(id, index_is_id=True)}
+        db = self.gui.library_view.model().db
+        dbspec = {}
+        for id in ids:
+            dbspec[id] = {'ondevice': db.ondevice(id, index_is_id=True)}
 
         # Calling gui2.tools:generate_catalog()
         ret = generate_catalog(self.gui, dbspec, ids, self.gui.device_manager,