diff --git a/docs/en_US/release_notes_4_15.rst b/docs/en_US/release_notes_4_15.rst
index 5139b724e..b8ac1e855 100644
--- a/docs/en_US/release_notes_4_15.rst
+++ b/docs/en_US/release_notes_4_15.rst
@@ -32,6 +32,7 @@ Bug fixes
 | `Issue #4483 <https://redmine.postgresql.org/issues/4483>`_ -  Ensure the number of jobs can be specified when backing up in directory format.
 | `Issue #4564 <https://redmine.postgresql.org/issues/4564>`_ -  Ensure Javascript errors during Query Tool execution are reported as such and not as Ajax errors.
 | `Issue #4610 <https://redmine.postgresql.org/issues/4610>`_ -  Suppress Enter key presses in Alertify dialogues when the come from Select2 controls to allow item selection with Enter.
+| `Issue #4647 <https://redmine.postgresql.org/issues/4647>`_ -  Ensure that units are respected when sorting by file size in the File dialog.
 | `Issue #4730 <https://redmine.postgresql.org/issues/4730>`_ -  Ensure all messages are retained in the Query Tool from long running queries.
 | `Issue #4734 <https://redmine.postgresql.org/issues/4734>`_ -  Updated documentation for the delete row button that only strikeout the row instead of deleting it.
 | `Issue #4779 <https://redmine.postgresql.org/issues/4779>`_ -  Updated documentation for the query tool toolbar buttons.
diff --git a/web/pgadmin/misc/file_manager/__init__.py b/web/pgadmin/misc/file_manager/__init__.py
index ec956ea57..160f3466f 100644
--- a/web/pgadmin/misc/file_manager/__init__.py
+++ b/web/pgadmin/misc/file_manager/__init__.py
@@ -62,7 +62,7 @@ encode_json = json.JSONEncoder().encode
 # utility functions
 # convert bytes type to human readable format
 def sizeof_fmt(num, suffix='B'):
-    for unit in ['', 'K', 'M', 'G', 'T', 'P', 'E', 'Z']:
+    for unit in ['', 'k', 'M', 'G', 'T', 'P', 'E', 'Z']:
         if abs(num) < 1024.0:
             return "%3.1f %s%s" % (num, unit, suffix)
         num /= 1024.0
diff --git a/web/pgadmin/misc/file_manager/static/js/utility.js b/web/pgadmin/misc/file_manager/static/js/utility.js
index 77acc5be7..e3fc81a9f 100644
--- a/web/pgadmin/misc/file_manager/static/js/utility.js
+++ b/web/pgadmin/misc/file_manager/static/js/utility.js
@@ -20,7 +20,7 @@
 define([
   'jquery', 'underscore', 'pgadmin.alertifyjs',
   'sources/gettext', 'sources/url_for', 'dropzone', 'sources/pgadmin',
-  'sources/csrf', 'tablesorter',
+  'sources/csrf', 'tablesorter', 'tablesorter-metric',
 ], function($, _, Alertify, gettext, url_for, Dropzone, pgAdmin, csrfToken) {
 
   /*---------------------------------------------------------
@@ -588,8 +588,8 @@ define([
             result += '<table id="contents" class="table table-bordered table-noouter-border table-bottom-border table-hover tablesorter file_listing_table">';
             result += '<thead><tr><th>';
             result += '<span>' + lg.name + '</span></th>';
-            result += '<th><span>' + lg.size + '</span></th><th>';
-            result += '<span>' + lg.modified + '</span></th></tr></thead>';
+            result += '<th class="sorter-metric" data-metric-name-full="byte|Byte|BYTE" data-metric-name-abbr="b|B"><span>' + lg.size + '</span></th>';
+            result += '<th class="sorter-shortDate"><span>' + lg.modified + '</span></th></tr></thead>';
             result += '<tbody>';
 
             Object.keys(data).sort(function keyOrder(x, y) {
@@ -675,8 +675,8 @@ define([
            */
             result += '<table id="contents" class="table table-bordered table-noouter-border table-bottom-border table-hover tablesorter file_listing_table file_listing_table_no_data">';
             result += '<thead><tr><th><span>' + lg.name + '</span></th>' +
-                    '<th><span>' + lg.size + '</span></th>' +
-                    '<th><span>' + lg.modified + '</span></th>' +
+                    '<th class="sorter-metric" data-metric-name-full="byte|Byte|BYTE" data-metric-name-abbr="b|B"><span>' + lg.size + '</span></th>' +
+                    '<th class="sorter-shortDate"><span>' + lg.modified + '</span></th>' +
                     '</tr></thead>' +
                     '<tbody></tbody>';
             result += '</table>';
@@ -690,13 +690,7 @@ define([
 
         // Add the new markup to the DOM.
         $('.fileinfo .file_listing').html(result);
-        $('.fileinfo .file_listing #contents').tablesorter({
-          headers: {
-            2: {
-              sorter: 'shortDate',
-            },
-          },
-        });
+        $('.fileinfo .file_listing #contents').tablesorter();
 
         // rename file/folder
         $('.file_manager button.rename').off().on('click', function(e) {
diff --git a/web/webpack.shim.js b/web/webpack.shim.js
index b4d3b8591..2e2b7ed41 100644
--- a/web/webpack.shim.js
+++ b/web/webpack.shim.js
@@ -155,6 +155,7 @@ var webpackShimConfig = {
     'snap.svg': path.join(__dirname, './node_modules/snapsvg/dist/snap.svg-min'),
     'spectrum': path.join(__dirname, './node_modules/spectrum-colorpicker/spectrum'),
     'mousetrap': path.join(__dirname, './node_modules/mousetrap'),
+    'tablesorter-metric': path.join(__dirname, './node_modules/tablesorter/dist/js/parsers/parser-metric.min'),
 
     // AciTree
     'jquery.acitree': path.join(__dirname, './node_modules/acitree/js/jquery.aciTree.min'),