diff --git a/addons/hr_holidays/report/holidays_summary_report.py b/addons/hr_holidays/report/holidays_summary_report.py
index 3fcff6838f1..d77e664c9e9 100644
--- a/addons/hr_holidays/report/holidays_summary_report.py
+++ b/addons/hr_holidays/report/holidays_summary_report.py
@@ -1,6 +1,8 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
+import calendar
+
 from datetime import timedelta
 from dateutil.relativedelta import relativedelta
 from odoo import api, fields, models
@@ -16,12 +18,15 @@ class HrHolidaySummaryReport(models.AbstractModel):
             'end_date': fields.Date.to_string(st_date + relativedelta(days=59)),
             'holiday_type': 'Confirmed and Approved' if holiday_type == 'both' else holiday_type
         }
+    
+    def _date_is_day_off(self, date):
+        return date.weekday() in (calendar.SATURDAY, calendar.SUNDAY,)
 
     def _get_day(self, start_date):
         res = []
         start_date = fields.Date.from_string(start_date)
         for x in range(0, 60):
-            color = '#ababab' if start_date.strftime('%a') == 'Sat' or start_date.strftime('%a') == 'Sun' else ''
+            color = '#ababab' if self._date_is_day_off(start_date) else ''
             res.append({'day_str': start_date.strftime('%a'), 'day': start_date.day , 'color': color})
             start_date = start_date + relativedelta(days=1)
         return res
@@ -48,7 +53,7 @@ class HrHolidaySummaryReport(models.AbstractModel):
         for index in range(0, 60):
             current = start_date + timedelta(index)
             res.append({'day': current.day, 'color': ''})
-            if current.strftime('%a') == 'Sat' or current.strftime('%a') == 'Sun':
+            if self._date_is_day_off(current) :
                 res[index]['color'] = '#ababab'
         # count and get leave summary details.
         holiday_type = ['confirm','validate'] if holiday_type == 'both' else ['confirm'] if holiday_type == 'Confirmed' else ['validate']