diff --git a/CHANGES.rst b/CHANGES.rst
index 65e18416ac..f8cb98df98 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -40,6 +40,9 @@ New features:
 
 Bug fixes:
 
+- Fixed getObjSize indexer for Python 3. #2526
+  [reinhardt]
+
 - Remove the devdependencies from bower.json - they are just used for running tests in mockup, not here.
   [sunew]
 
diff --git a/Products/CMFPlone/CatalogTool.py b/Products/CMFPlone/CatalogTool.py
index 6ca37339b1..c972acf0cd 100644
--- a/Products/CMFPlone/CatalogTool.py
+++ b/Products/CMFPlone/CatalogTool.py
@@ -244,7 +244,7 @@ def getObjSize(obj):
         if size < SIZE_CONST[smaller]:
             return '1 %s' % smaller
         for c in SIZE_ORDER:
-            if size / SIZE_CONST[c] > 0:
+            if size // SIZE_CONST[c] > 0:
                 break
         return '%.1f %s' % (float(size / float(SIZE_CONST[c])), c)
     return size
diff --git a/Products/CMFPlone/tests/testCatalogTool.py b/Products/CMFPlone/tests/testCatalogTool.py
index a5eec9d5f3..5f491ef7e9 100644
--- a/Products/CMFPlone/tests/testCatalogTool.py
+++ b/Products/CMFPlone/tests/testCatalogTool.py
@@ -1303,14 +1303,20 @@ def test_provided(self):
         self.assertTrue(IIndexableObjectWrapper.providedBy(w))
         self.assertTrue(IContentish.providedBy(w))
 
-    def test_getObjSize(self):
+    def test_getObjSize_KB(self):
         from Products.CMFPlone.CatalogTool import getObjSize
         get_size = getObjSize.callable
-        # FIXME: getObjSize die not count text in DX
         self.doc.text = RichTextValue('a' * 1000)
         self.doc.reindexObject()
         self.assertEqual(get_size(self.doc), '1 KB')
 
+    def test_getObjSize_MB(self):
+        from Products.CMFPlone.CatalogTool import getObjSize
+        get_size = getObjSize.callable
+        self.doc.text = RichTextValue('a' * 6000000)
+        self.doc.reindexObject()
+        self.assertEqual(get_size(self.doc), '5.7 MB')
+
     def test_uuid(self):
         alsoProvides(self.doc, IAttributeUUID)
         notify(ObjectCreatedEvent(self.doc))