diff --git a/source/reference/mongo-shell.txt b/source/reference/mongo-shell.txt
index 5d001026d29..2a24c21428e 100644
--- a/source/reference/mongo-shell.txt
+++ b/source/reference/mongo-shell.txt
@@ -554,7 +554,7 @@ The following table displays some miscellaneous methods:
      - **Description**
 
    * - ``Object.bsonsize(<document>)``
-     - Prints the :term:`BSON` size of a <document>
+     - Prints the :term:`BSON` size of a <document> in bytes
 
 See the `MongoDB JavaScript API Documentation
 <http://api.mongodb.org/js/index.html>`_ for a full list of JavaScript