diff --git a/CHANGES.rst b/CHANGES.rst
index f8cb98df98..b500995ef6 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -17,6 +17,9 @@ Breaking changes:
 
 New features:
 
+- Factored out format_size method for replacing getObjSize.py. #1801
+  [reinhardt]
+
 - Update TinyMCE to 4.7.13
   [erral]
 
diff --git a/Products/CMFPlone/CatalogTool.py b/Products/CMFPlone/CatalogTool.py
index c972acf0cd..4c8cf8501d 100644
--- a/Products/CMFPlone/CatalogTool.py
+++ b/Products/CMFPlone/CatalogTool.py
@@ -219,17 +219,10 @@ def getObjPositionInParent(obj):
 SIZE_ORDER = ('GB', 'MB', 'KB')
 
 
-@indexer(Interface)
-def getObjSize(obj):
-    """ Helper method for catalog based folder contents.
-    """
+def format_size(size):
+    """ Get a human readable size string. """
     smaller = SIZE_ORDER[-1]
 
-    if base_hasattr(obj, 'get_size'):
-        size = obj.get_size()
-    else:
-        size = 0
-
     # if the size is a float, then make it an int
     # happens for large files
     try:
@@ -250,6 +243,18 @@ def getObjSize(obj):
     return size
 
 
+@indexer(Interface)
+def getObjSize(obj):
+    """ Helper method for catalog based folder contents.
+    """
+    if base_hasattr(obj, 'get_size'):
+        size = obj.get_size()
+    else:
+        size = 0
+
+    return format_size(size)
+
+
 @indexer(Interface)
 def is_folderish(obj):
     """Should this item be treated as a folder?