diff --git a/src/opnsense/mvc/app/controllers/OPNsense/Diagnostics/FirewallController.php b/src/opnsense/mvc/app/controllers/OPNsense/Diagnostics/FirewallController.php
index 3e5c1455ccb..ffdd8047c4d 100644
--- a/src/opnsense/mvc/app/controllers/OPNsense/Diagnostics/FirewallController.php
+++ b/src/opnsense/mvc/app/controllers/OPNsense/Diagnostics/FirewallController.php
@@ -29,6 +29,7 @@
 namespace OPNsense\Diagnostics;
 
 use OPNsense\Base\IndexController;
+use OPNsense\Core\Config;
 
 /**
  * Class FirewallController
@@ -61,6 +62,7 @@ protected function templateCSSIncludes()
     public function logAction()
     {
         $this->view->pick('OPNsense/Diagnostics/fw_log');
+        $this->view->timefmt = !empty(Config::getInstance()->object()->syslog->timefmt) ? Config::getInstance()->object()->syslog->timefmt : 'Log_Raw';
     }
     /**
      * firewall statistical view
diff --git a/src/opnsense/mvc/app/controllers/OPNsense/Diagnostics/LogController.php b/src/opnsense/mvc/app/controllers/OPNsense/Diagnostics/LogController.php
index 588a5de97ff..9480faca6a3 100644
--- a/src/opnsense/mvc/app/controllers/OPNsense/Diagnostics/LogController.php
+++ b/src/opnsense/mvc/app/controllers/OPNsense/Diagnostics/LogController.php
@@ -29,6 +29,7 @@
 namespace OPNsense\Diagnostics;
 
 use OPNsense\Base\IndexController;
+use OPNsense\Core\Config;
 
 /**
  * @inherit
@@ -42,6 +43,7 @@ public function renderPage($module, $scope)
         $this->view->scope = htmlspecialchars($scope, ENT_QUOTES | ENT_HTML401);
         $this->view->service = '';
         $this->view->default_log_severity = 'Warning';
+        $this->view->timefmt = !empty(Config::getInstance()->object()->OPNsense->Syslog->general->timefmt) ? Config::getInstance()->object()->OPNsense->Syslog->general->timefmt : 'Log_Raw';
 
         $service = $module == 'core' ? $scope : $module;
 
diff --git a/src/opnsense/mvc/app/controllers/OPNsense/Firewall/AliasController.php b/src/opnsense/mvc/app/controllers/OPNsense/Firewall/AliasController.php
index 291799fc6ec..875956aed9d 100644
--- a/src/opnsense/mvc/app/controllers/OPNsense/Firewall/AliasController.php
+++ b/src/opnsense/mvc/app/controllers/OPNsense/Firewall/AliasController.php
@@ -29,6 +29,7 @@
 namespace OPNsense\Firewall;
 
 use OPNsense\Base\IndexController;
+use OPNsense\Core\Config;
 
 /**
  * @package OPNsense\Firewall
@@ -41,5 +42,6 @@ public function indexAction($selected = null)
         $this->view->selected_alias = $selected;
         $this->view->formGeoIPSettings = $this->getForm("geoIPSettings");
         $this->view->pick('OPNsense/Firewall/alias');
+        $this->view->timefmt = !empty(Config::getInstance()->object()->syslog->timefmt) ? Config::getInstance()->object()->syslog->timefmt : 'Log_Raw';
     }
 }
diff --git a/src/opnsense/mvc/app/controllers/OPNsense/Syslog/forms/local.xml b/src/opnsense/mvc/app/controllers/OPNsense/Syslog/forms/local.xml
index 3dc3a37362b..a0932136e1f 100644
--- a/src/opnsense/mvc/app/controllers/OPNsense/Syslog/forms/local.xml
+++ b/src/opnsense/mvc/app/controllers/OPNsense/Syslog/forms/local.xml
@@ -17,4 +17,12 @@
         <type>text</type>
         <help>Maximum file size per log file. When set and a log file exceeds the amount specified, it will be rotated.</help>
     </field>
+    <field>
+      <id>syslog.general.timefmt</id>
+      <label>Time Display Format</label>
+      <type>dropdown</type>
+      <help><![CDATA[Time format to display on system log pages.<br>
+        (boot log does not include timezone)]]>
+      </help>
+    </field>
 </form>
diff --git a/src/opnsense/mvc/app/models/OPNsense/Syslog/Syslog.xml b/src/opnsense/mvc/app/models/OPNsense/Syslog/Syslog.xml
index 6a63bd535de..1a31f452e8f 100644
--- a/src/opnsense/mvc/app/models/OPNsense/Syslog/Syslog.xml
+++ b/src/opnsense/mvc/app/models/OPNsense/Syslog/Syslog.xml
@@ -16,6 +16,18 @@
                 <Required>Y</Required>
             </maxpreserve>
             <maxfilesize type="IntegerField"/>
+            <timefmt type="OptionField">
+                <Default>Log_Raw</Default>
+                <Required>Y</Required>
+                  <OptionValues>
+                      <Web_GUI_Language>Web GUI Language (MMM DD hh:mm:ss)</Web_GUI_Language>
+                      <Client_Locale>Client Locale (MMM DD hh:mm:ss)</Client_Locale>
+                      <Log_Raw>Log Raw (YYYY-MM-DDThh:mm:ss+/-hh:mm)</Log_Raw>
+                      <Log_Long>Log Long (YYYY-MM-DD hh:mm:ss+/-hh)</Log_Long>
+                      <Log_Long_No_TZ>Log Long w/o TZ (YYYY-MM-DD hh:mm:ss)</Log_Long_No_TZ>
+                      <Log_Short>Log Short (MM-DD hh:mm:ss)</Log_Short>
+                  </OptionValues>
+            </timefmt>
         </general>
         <destinations>
             <destination type="ArrayField">
diff --git a/src/opnsense/mvc/app/views/OPNsense/Diagnostics/fw_log.volt b/src/opnsense/mvc/app/views/OPNsense/Diagnostics/fw_log.volt
index c95e68bdff7..4ef88f14024 100644
--- a/src/opnsense/mvc/app/views/OPNsense/Diagnostics/fw_log.volt
+++ b/src/opnsense/mvc/app/views/OPNsense/Diagnostics/fw_log.volt
@@ -27,6 +27,17 @@
 <script>
     'use strict';
 
+    // Time display format: Use or override log raw time format
+    var timefmt = 
+        "{{ timefmt }}" == 'Web_GUI_Language' ? "{{ langcode }}"
+      : "{{ timefmt }}" == 'Client_Locale' ? 'default'
+      : "{{ timefmt }}";
+
+    // Implement as Intl.DateTimeFormat object for efficiency (toLocaleString).
+    if (timefmt == "{{ langcode }}" || timefmt == 'default') {
+        var IDTF_obj = new Intl.DateTimeFormat(timefmt, { month:'short', day:'2-digit', hour:'numeric', hourCycle:'h23', minute: 'numeric', second: 'numeric'});
+    }
+
     $( document ).ready(function() {
         var field_type_icons = {
           'binat': 'fa-exchange',
@@ -258,6 +269,22 @@
                             } else {
                                 record['interface_name'] = record.interface;
                             }
+                            switch (timefmt) {
+                                case 'Log_Raw':
+                                    record['__timestamp__'] = record['__timestamp__'];
+                                    break;
+                                case 'Log_Long':
+                                    record['__timestamp__'] = record['__timestamp__'].substring(0,22).replace('T', ' ');
+                                    break;
+                                case 'Log_Long_No_TZ':
+                                    record['__timestamp__'] = record['__timestamp__'].substring(0,19).replace('T', ' ');
+                                    break;
+                                case 'Log_Short':
+                                    record['__timestamp__'] = record['__timestamp__'].substring(5,19).replace('T', ' ');
+                                    break;
+                                default:
+                                    record['__timestamp__'] = IDTF_obj.format(new Date(record['__timestamp__'])).replace(/[.,]/g, '');
+                            }
                             log_tr.data('details', record);
                             log_tr.hide();
                             $.each(record_spec, function(idx, field){
diff --git a/src/opnsense/mvc/app/views/OPNsense/Diagnostics/log.volt b/src/opnsense/mvc/app/views/OPNsense/Diagnostics/log.volt
index dce66df6e55..47de5cd235f 100644
--- a/src/opnsense/mvc/app/views/OPNsense/Diagnostics/log.volt
+++ b/src/opnsense/mvc/app/views/OPNsense/Diagnostics/log.volt
@@ -25,6 +25,17 @@
  #}
 
 <script>
+    // Time display format: Use or override log raw time format
+    var timefmt = 
+        "{{ timefmt }}" == 'Web_GUI_Language' ? "{{ langcode }}"
+      : "{{ timefmt }}" == 'Client_Locale' ? 'default'
+      : "{{ timefmt }}";
+
+    // Implement as Intl.DateTimeFormat object for efficiency (toLocaleString).
+    if (timefmt == "{{ langcode }}" || timefmt == 'default') {
+        var IDTF_obj = new Intl.DateTimeFormat(timefmt, { month:'short', day:'2-digit', hour:'numeric', hourCycle:'h23', minute: 'numeric', second: 'numeric'});
+    }
+
     $( document ).ready(function() {
       var filter_exact = false;
       let s_filter_val = '{{default_log_severity}}';
@@ -64,6 +75,27 @@
                           return "";
                       }
                   },
+                  timestamp: function (column, row) {
+                      if (row[column.id]) {
+                          switch (timefmt) {
+                              case 'Log_Raw':
+                                  return row[column.id];
+                                  break;
+                              case 'Log_Long':
+                                  return row[column.id].substring(0,22).replace('T', ' ');
+                                  break;
+                              case 'Log_Long_No_TZ':
+                                  return row[column.id].substring(0,19).replace('T', ' ');
+                                  break;
+                              case 'Log_Short':
+                                  return row[column.id].substring(5,19).replace('T', ' ');
+                                  break;
+                              default:
+                                  return IDTF_obj.format(new Date(row[column.id])).replace(/[.,]/g, '');
+                          }
+                      }
+                      return row[column.id];
+                  },
               },
               requestHandler: function(request){
                   if ( $('#severity_filter').val().length > 0) {
@@ -214,7 +246,7 @@
                 <table id="grid-log" class="table table-condensed table-hover table-striped table-responsive">
                     <thead>
                     <tr>
-                        <th data-column-id="timestamp" data-width="11em" data-type="string">{{ lang._('Date') }}</th>
+                        <th data-column-id="timestamp" data-width="9.5em" data-formatter="timestamp" data-type="string">{{ lang._('Date') }}</th>
                         <th data-column-id="facility" data-type="string" data-visible="false">{{ lang._('Facility') }}</th>
                         <th data-column-id="severity" data-type="string" data-width="2em">{{ lang._('Severity') }}</th>
                         <th data-column-id="process_name" data-width="2em" data-type="string">{{ lang._('Process') }}</th>
diff --git a/src/opnsense/mvc/app/views/OPNsense/Firewall/alias.volt b/src/opnsense/mvc/app/views/OPNsense/Firewall/alias.volt
index c81e4fd276b..3cbaff2673a 100644
--- a/src/opnsense/mvc/app/views/OPNsense/Firewall/alias.volt
+++ b/src/opnsense/mvc/app/views/OPNsense/Firewall/alias.volt
@@ -64,6 +64,17 @@
 
 </style>
 <script>
+    // Time display format: Use or override log raw time format
+    var timefmt = 
+        "{{ timefmt }}" == 'Web_GUI_Language' ? "{{ langcode }}"
+      : "{{ timefmt }}" == 'Client_Locale' ? 'default'
+      : "{{ timefmt }}";
+
+    // Implement as Intl.DateTimeFormat object for efficiency (toLocaleString).
+    if (timefmt == "{{ langcode }}" || timefmt == 'default') {
+        var IDTF_obj = new Intl.DateTimeFormat(timefmt, { month:'short', day:'2-digit', hour:'numeric', hourCycle:'h23', minute: 'numeric', second: 'numeric'});
+    }
+
     $( document ).ready(function() {
         $("#grid-aliases").UIBootgrid({
             search:'/api/firewall/alias/searchItem',
@@ -116,8 +127,21 @@
                         }
                     },
                     timestamp: function (column, row) {
-                        if (row[column.id] && row[column.id].includes('.')) {
-                            return row[column.id].split('.')[0].replace('T', ' ');
+                        if (row[column.id]) {
+                            switch (timefmt) {
+                                case 'Log_Raw':
+                                    return row[column.id];
+                                    break;
+                                case 'Log_Long':
+                                case 'Log_Long_No_TZ':
+                                    return row[column.id].substring(0,19).replace('T', ' ');
+                                    break;
+                                case 'Log_Short':
+                                    return row[column.id].substring(5,19).replace('T', ' ');
+                                    break;
+                                default:
+                                    return IDTF_obj.format(new Date(row[column.id])).replace(/[.,]/g, '');
+                            }
                         }
                         return row[column.id];
                     }
diff --git a/src/www/system_advanced_firewall.php b/src/www/system_advanced_firewall.php
index 05b51a9aea1..e53d2aa8ea9 100644
--- a/src/www/system_advanced_firewall.php
+++ b/src/www/system_advanced_firewall.php
@@ -71,6 +71,10 @@
     $pconfig['logoutboundnat'] = !empty($config['syslog']['logoutboundnat']);
     $pconfig['logbogons'] = empty($config['syslog']['nologbogons']);
     $pconfig['logprivatenets'] = empty($config['syslog']['nologprivatenets']);
+
+    // Time display format: Use or override log raw time format
+    $pconfig['timefmt'] = !empty($config['syslog']['timefmt']) ? $config['syslog']['timefmt'] : 'Log_Raw';
+
 } elseif ($_SERVER['REQUEST_METHOD'] === 'POST') {
     $pconfig = $_POST;
     $input_errors = array();
@@ -262,6 +266,13 @@
         $config['syslog']['nologprivatenets'] = empty($pconfig['logprivatenets']);
         $config['syslog']['logoutboundnat'] = !empty($pconfig['logoutboundnat']);
 
+        // Time display format: Use or override log raw time format
+        if (!empty($pconfig['timefmt']) && $pconfig['timefmt'] != 'Log_Raw') {
+            $config['syslog']['timefmt'] = $pconfig['timefmt'];
+        } else {
+            unset($config['syslog']['timefmt']);
+        }
+
         write_config();
 
         $savemsg = get_std_save_message();
@@ -538,6 +549,33 @@
                   <?=gettext("Log packets blocked by 'Block Private Networks' rules");?>
                 </td>
               </tr>
+<?php
+    // Time formats (language locales)
+    $locales = array(
+        'Web_GUI_Language' => gettext('Web GUI Language (MMM DD hh:mm:ss)'),
+        'Client_Locale' => gettext('Client Locale (MMM DD hh:mm:ss)'),
+        'Log_Raw' => gettext('Log Raw (YYYY-MM-DDThh:mm:ss+/-hh:mm)'),
+        'Log_Long' => gettext('Log Long (YYYY-MM-DD hh:mm:ss+/-hh)'),
+        'Log_Long_No_TZ' => gettext('Log Long w/o TZ (YYYY-MM-DD hh:mm:ss)'),
+        'Log_Short' => gettext('Log Short (MM-DD hh:mm:ss)'),
+    );
+?>
+                  <tr>
+                    <td><a id="help_for_timefmt" href="#" class="showhelp"><i class="fa fa-info-circle"></i></a> <?=gettext('Time display format') ?></td>
+                    <td>
+                      <label for="timefmt">
+                        <select id="timefmt" name="timefmt" class="selectpicker" data-style="btn-default">
+<?php foreach ($locales as $lcode => $ldesc): ?>
+            <option value="<?= html_safe($lcode) ?>" <?= $lcode == $pconfig['timefmt'] ? 'selected="selected"' : '' ?>><?= html_safe($ldesc) ?></option>
+<?php endforeach ?>
+                        </select>
+                      </label>
+                      <div class="hidden" data-for="help_for_timefmt">
+                        <?=gettext('Time format to display on firewall log pages and aliases last updated.');?><br>
+                        <?=gettext('(aliases last updated does not include timezone)');?>
+                      </div>
+                    </td>
+                  </tr>
             </table>
           </div>
           <div class="content-box tab-content table-responsive __mb">
diff --git a/src/www/widgets/widgets/log.widget.php b/src/www/widgets/widgets/log.widget.php
index 24b3a2e9985..9ad00337b35 100644
--- a/src/www/widgets/widgets/log.widget.php
+++ b/src/www/widgets/widgets/log.widget.php
@@ -63,6 +63,13 @@
         unset($config['widgets']['filterlogentriesinterfaces']);
     }
 
+    // Time display format: Use or override log raw time format
+    if (!empty($pconfig['timefmt']) && $pconfig['timefmt'] != 'Log_Raw') {
+        $config['widgets']['filterlogentriestimefmt'] = $pconfig['timefmt'];
+    } else {
+        unset($config['widgets']['filterlogentriestimefmt']);
+    }
+
     write_config('Saved Filter Log Entries via Dashboard');
     header(url_safe('Location: /index.php'));
     exit;
@@ -73,8 +80,23 @@
 $nentriesacts = isset($config['widgets']['filterlogentriesacts']) ?  explode(" ", $config['widgets']['filterlogentriesacts']) : array('Pass', 'Block', 'Reject');
 $nentriesinterfaces = isset($config['widgets']['filterlogentriesinterfaces']) ? $config['widgets']['filterlogentriesinterfaces'] : '';
 
+// Time display format: Use or override log raw time format
+$langcode = !empty($config['system']['language']) ? $config['system']['language'] : 'en_US';
+$timefmt = !empty($config['widgets']['filterlogentriestimefmt']) ? $config['widgets']['filterlogentriestimefmt'] : 'Log_Raw';
+
 ?>
 <script>
+    // Time display format: Use or override log raw time format
+    var timefmt = 
+        "<?= $timefmt ?>" == 'Web_GUI_Language' ? "<?= $langcode ?>".replaceAll('_', '-')
+      : "<?= $timefmt ?>" == 'Client_Locale' ? 'default'
+      : "<?= $timefmt ?>";
+
+    // Implement as Intl.DateTimeFormat object for efficiency (toLocaleString).
+    if (timefmt == "<?= $langcode ?>".replaceAll('_', '-') || timefmt == 'default') {
+        var IDTF_obj = new Intl.DateTimeFormat(timefmt, { month:'short', day:'2-digit', hour:'numeric', hourCycle:'h23', minute: 'numeric'});
+    }
+
     $("#dashboard_container").on("WidgetsReady", function() {
         // needed to display the widget settings menu
         $("#log-configure").removeClass("disabled");
@@ -142,7 +164,22 @@ function fetch_log(){
                                         }
                                         break;
                                     case 'time':
-                                        log_td.text(record[column_name].replace(/:[0-9]{2}$/, ''));
+                                        switch (timefmt) {
+                                            case 'Log_Raw':
+                                                log_td.text(record[column_name]);
+                                                break;
+                                            case 'Log_Long':
+                                                log_td.text(record[column_name].substring(0,22).replace('T', ' '));
+                                                break;
+                                            case 'Log_Long_No_TZ':
+                                                log_td.text(record[column_name].substring(0,19).replace('T', ' '));
+                                                break;
+                                            case 'Log_Short':
+                                                log_td.text(record[column_name].substring(5,16).replace('T', ' '));
+                                                break;
+                                            default:
+                                                log_td.text(IDTF_obj.format(new Date(record[column_name])).replace(/[.,]/g, ''));
+                                        }
                                         break;
                                     case 'interface':
                                         if (interface_descriptions[record[column_name]] != undefined) {
@@ -214,6 +251,23 @@ function fetch_log(){
           <label for="filterlogentriesinterfaces"><?= gettext('Interfaces to display:'); ?></label><br/>
           <select id="filterlogentriesinterfaces" name="filterlogentriesinterfaces[]" class="selectpicker_widget" multiple="multiple" title=<?= gettext('All'); ?>>
           </select><br/><br/>
+<?php
+    // Time formats (language locales)
+    $locales = array(
+        'Web_GUI_Language' => gettext('Web GUI Language (MMM DD hh:mm)'),
+        'Client_Locale' => gettext('Client Locale (MMM DD hh:mm)'),
+        'Log_Raw' => gettext('Log Raw (YYYY-MM-DDThh:mm:ss+/-hh:mm)'),
+        'Log_Long' => gettext('Log Long (YYYY-MM-DD hh:mm:ss+/-hh)'),
+        'Log_Long_No_TZ' => gettext('Log Long w/o TZ (YYYY-MM-DD hh:mm:ss)'),
+        'Log_Short' => gettext('Log Short (MM-DD hh:mm)'),
+    );
+?>
+          <label for="timefmt"><?= gettext('Time display format:') ?></label><br/>
+          <select id="timefmt" name="timefmt" class="selectpicker_widget">
+<?php foreach ($locales as $lcode => $ldesc): ?>
+            <option value="<?= html_safe($lcode) ?>" <?= $lcode == $timefmt ? 'selected="selected"' : '' ?>><?= html_safe($ldesc) ?></option>
+<?php endforeach ?>
+          </select><br/>
           <table style="width:348px">
             <tr>
               <td><label for="actblock"><input id="actblock" name="actblock" type="checkbox" value="Block" <?=in_array('Block', $nentriesacts) ? "checked=\"checked\"" : "";?> /><?= gettext('Block') ?></label></td>
diff --git a/src/www/widgets/widgets/system_log.widget.php b/src/www/widgets/widgets/system_log.widget.php
index 4c40ffaedbc..37b7e51a277 100644
--- a/src/www/widgets/widgets/system_log.widget.php
+++ b/src/www/widgets/widgets/system_log.widget.php
@@ -48,6 +48,13 @@
         $config['widgets']['systemlogseverity'] = $_POST['systemlogseverity'];
     }
 
+    // Time display format: Use or override log raw time format
+    if (!empty($_POST['timefmt']) && $_POST['timefmt'] != 'Log_Raw') {
+        $config['widgets']['systemlogentriestimefmt'] = $_POST['timefmt'];
+    } else {
+        unset($config['widgets']['systemlogentriestimefmt']);
+    }
+
     if (count($input_errors) == 0) {
       $config['widgets']['systemlogentriesfilter'] = $_POST['systemlogentriesfilter'];
       write_config("System Log Widget settings saved");
@@ -67,6 +74,11 @@
 $systemlogupdateinterval = isset($config['widgets']['systemlogupdateinterval']) ? $config['widgets']['systemlogupdateinterval'] : 10;
 $systemlogseverity = isset($config['widgets']['systemlogseverity']) ? $config['widgets']['systemlogseverity'] : "Debug";
 $systemlogentriesfilter = isset($config['widgets']['systemlogentriesfilter']) ? $config['widgets']['systemlogentriesfilter'] : "";
+
+// Time display format: Use or override log raw time format
+$langcode = !empty($config['system']['language']) ? $config['system']['language'] : 'en_US';
+$timefmt = !empty($config['widgets']['systemlogentriestimefmt']) ? $config['widgets']['systemlogentriestimefmt'] : 'Log_Raw';
+
 if (isset($_COOKIE['inputerrors'])) {
     foreach ($_COOKIE['inputerrors'] as $i => $value) {
         $input_errors[] = $value;
@@ -110,6 +122,28 @@
           </select>
         </td>
       </tr>
+<?php
+    // Time formats (language locales)
+    $locales = array(
+        'Web_GUI_Language' => gettext('Web GUI Language (MMM DD hh:mm)'),
+        'Client_Locale' => gettext('Client Locale (MMM DD hh:mm)'),
+        'Log_Raw' => gettext('Log Raw (YYYY-MM-DDThh:mm:ss+/-hh:mm)'),
+        'Log_Long' => gettext('Log Long (YYYY-MM-DD hh:mm:ss+/-hh)'),
+        'Log_Long_No_TZ' => gettext('Log Long w/o TZ (YYYY-MM-DD hh:mm:ss)'),
+        'Log_Short' => gettext('Log Short (MM-DD hh:mm)'),
+    );
+?>
+      <tr>
+        <td><?= gettext('Time display format:') ?></td>
+        <td colspan="2">
+          <select id="timefmt" name="timefmt">
+<?php foreach ($locales as $lcode => $ldesc): ?>
+            <option value="<?= html_safe($lcode) ?>" <?= $lcode == $timefmt ? 'selected="selected"' : '' ?>><?= html_safe($ldesc) ?></option>
+<?php endforeach ?>
+          </select>
+        </td>
+        <td></td>
+      </tr>
       <tr>
         <td><?= gettext('Log query filter:') ?></td>
         <td>
@@ -139,6 +173,16 @@
 </div>
 
 <script>
+    // Time display format: Use or override log raw time format
+    var timefmt = 
+        "<?= $timefmt ?>" == 'Web_GUI_Language' ? "<?= $langcode ?>".replaceAll('_', '-')
+      : "<?= $timefmt ?>" == 'Client_Locale' ? 'default'
+      : "<?= $timefmt ?>";
+
+    // Implement as Intl.DateTimeFormat object for efficiency (toLocaleString).
+    if (timefmt == "<?= $langcode ?>".replaceAll('_', '-') || timefmt == 'default') {
+        var IDTF_obj = new Intl.DateTimeFormat(timefmt, { month:'short', day:'2-digit', hour:'numeric', hourCycle:'h23', minute: 'numeric'});
+    }
 
             function fetch_system_log(rowCount, refresh_interval_ms, requestSeverity) {
                 //it is more correct to pass the filter value to the function (without searching the value every time). but this method allows to "live" test the filter value before saving
@@ -160,6 +204,22 @@ function fetch_system_log(rowCount, refresh_interval_ms, requestSeverity) {
                                 system_log_tr += '<tr class="system_log_entry"><td style="text-align: center;"><?=html_safe(gettext("No results found!")); ?></td></tr>';
                             } else {
                                 while ((entry = data.rows.shift())) {
+                                    switch (timefmt) {
+                                        case 'Log_Raw':
+                                            entry['timestamp'] = entry['timestamp'];
+                                            break;
+                                        case 'Log_Long':
+                                            entry['timestamp'] = entry['timestamp'].substring(0,22).replace('T', ' ');
+                                            break;
+                                        case 'Log_Long_No_TZ':
+                                            entry['timestamp'] = entry['timestamp'].substring(5,16).replace('T', ' ');
+                                            break;
+                                        case 'Log_Short':
+                                            entry['timestamp'] = entry['timestamp'].substring(5,16).replace('T', ' ');
+                                            break;
+                                        default:
+                                            entry['timestamp'] = IDTF_obj.format(new Date(entry['timestamp'])).replace(/[.,]/g, '');
+                                    }
                                 system_log_tr += '<tr class="system_log_entry"><td style="white-space: nowrap;">' + entry['timestamp'] + '<br>[' + entry['severity'] + ']<br>' + entry['process_name'].split('[')[0] + '</td><td>' + entry['line'] + '</td></tr>';
                                 }
                             }