diff --git a/src/calibre/db/fields.py b/src/calibre/db/fields.py
index 4836502c81..bf27e5287c 100644
--- a/src/calibre/db/fields.py
+++ b/src/calibre/db/fields.py
@@ -77,7 +77,10 @@ class Field(object):
         self.default_value = {} if name == 'identifiers' else () if self.is_multiple else None
         self.category_formatter = type(u'')
         if dt == 'rating':
-            self.category_formatter = partial(rating_to_stars, allow_half_stars=self.metadata['display'].get('allow_half_stars', False))
+            if self.metadata['display'].get('allow_half_stars', False):
+                self.category_formatter = lambda x: rating_to_stars(x, True)
+            else:
+                self.category_formatter = rating_to_stars
         elif name == 'languages':
             self.category_formatter = calibre_langcode_to_name
         self.writer = Writer(self)
diff --git a/src/calibre/ebooks/metadata/__init__.py b/src/calibre/ebooks/metadata/__init__.py
index 1b80da5d09..67ad6c5c92 100644
--- a/src/calibre/ebooks/metadata/__init__.py
+++ b/src/calibre/ebooks/metadata/__init__.py
@@ -397,11 +397,9 @@ def check_doi(doi):
 def rating_to_stars(value, allow_half_stars=False, star=u'★', half=u'½'):
     r = max(0, min(int(value or 0), 10))
     if allow_half_stars:
-        ans = u'★' * (r // 2)
+        ans = star * (r // 2)
         if r % 2:
-            ans += u'½'
+            ans += half
     else:
-        ans = u'★' * int(r/2.0)
+        ans = star * int(r/2.0)
     return ans
-
-
diff --git a/src/calibre/gui2/tag_browser/model.py b/src/calibre/gui2/tag_browser/model.py
index 456004f126..e613a88ed3 100644
--- a/src/calibre/gui2/tag_browser/model.py
+++ b/src/calibre/gui2/tag_browser/model.py
@@ -15,6 +15,7 @@ from PyQt5.Qt import (QAbstractItemModel, QIcon, QFont, Qt,
         QMimeData, QModelIndex, pyqtSignal, QObject)
 
 from calibre.constants import config_dir
+from calibre.ebooks.metadata import rating_to_stars
 from calibre.gui2 import gprefs, config, error_dialog, file_icon_provider
 from calibre.db.categories import Tag
 from calibre.utils.config import tweaks
@@ -1294,6 +1295,7 @@ class TagsModel(QAbstractItemModel):  # {{{
         # They will be 'checked' in both places, but we want to put the node
         # into the search string only once. The nodes_seen set helps us do that
         nodes_seen = set()
+        stars = rating_to_stars(3, True)
 
         node_searches = {TAG_SEARCH_STATES['mark_plus']       : 'true',
                          TAG_SEARCH_STATES['mark_plusplus']   : '.true',
@@ -1351,8 +1353,11 @@ class TagsModel(QAbstractItemModel):  # {{{
                     if self.db.field_metadata[tag.category]['is_csp']:
                         add_colon = True
 
-                    if tag.name and tag.name[0] in u'★½':  # char is a star or a half. Assume rating
-                        ans.append('%s%s:%s'%(prefix, category, len(tag.name)))
+                    if tag.name and tag.name[0] in stars:  # char is a star or a half. Assume rating
+                        rnum = len(tag.name)
+                        if tag.name.endswith(stars[-1]):
+                            rnum = '%s.5' % (rnum - 1)
+                        ans.append('%s%s:%s'%(prefix, category, rnum))
                     else:
                         name = tag.original_name
                         use_prefix = tag.state in [TAG_SEARCH_STATES['mark_plusplus'],
diff --git a/src/pyj/book_list/search.pyj b/src/pyj/book_list/search.pyj
index 8a53314365..4c3ccd6053 100644
--- a/src/pyj/book_list/search.pyj
+++ b/src/pyj/book_list/search.pyj
@@ -9,6 +9,7 @@ from elementmaker import E
 from gettext import gettext as _
 from widgets import create_button, create_spinner, Breadcrumbs
 from modals import show_modal
+from utils import rating_to_stars
 from book_list.globals import get_boss, get_session_data
 from book_list.theme import get_color, get_font_size
 
@@ -224,6 +225,7 @@ class SearchPanel:
             return ''
 
         search_state = {'plus':'true', 'plusplus':'.true', 'minus':'false', 'minusminus':'.false'}[state]
+        stars = rating_to_stars(3, True)
 
         if item.is_category:
             category = item.category
@@ -256,9 +258,12 @@ class SearchPanel:
             return expr
 
         category = 'tags' if item.category is 'news' else item.category
-        if item.name and item.name[0] in '★½':
+        if item.name and item.name[0] in stars:
             # Assume ratings
-            expr = '{}:{}'.format(category, item.name.length)
+            rnum = item.name.length
+            if item.name.endswith(stars[-1]):
+                rnum = '{}.5'.format(rnum - 1)
+            expr = '{}:{}'.format(category, rnum)
         else:
             fm = self.interface_data.field_metadata[item.category]
             suffix = ':' if fm and fm.is_csp else ''
diff --git a/src/pyj/utils.pyj b/src/pyj/utils.pyj
index f6905cdcf2..837f189736 100644
--- a/src/pyj/utils.pyj
+++ b/src/pyj/utils.pyj
@@ -69,6 +69,16 @@ def fmt_sidx(val, fmt='{:.2f}', use_roman=True):
         return int(val) + ''
     return fmt.format(float(val))
 
+def rating_to_stars(value, allow_half_stars=False, star='★', half='½'):
+    r = max(0, min(int(value or 0), 10))
+    if allow_half_stars:
+        ans = star.repeat(r // 2)
+        if r % 2:
+            ans += half
+    else:
+        ans = star.repeat(int(r/2.0))
+    return ans
+
 def human_readable(size, sep=' '):
     divisor, suffix = 1, "B"
     for i, candidate in enumerate(('B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB')):
@@ -142,5 +152,8 @@ def uniq(vals):
     return ans
 
 if __name__ is '__main__':
+    from pythonize import strings
+    strings()
+    print(rating_to_stars(3, True))
     print(fmt_sidx(10), fmt_sidx(1.2))
     print(list(map(human_readable, [1, 1024.0, 1025, 1024*1024*2.3])))