New Zealand

Business days calculator

Count working days in New Zealand (no Saturdays, Sundays or holidays)

Between two dates Add business days

Count working days in New Zealand (no Saturdays, Sundays or holidays)

This month Next 30 days Until year end +10 business days +15 business days +30 business days

12863

business days

From June 2, 1975 to July 26, 2026

We swapped the dates because “to” was earlier than “from”.

Business day 12863
Weekend 5338
Holidays 482

18683 days in the period

18683

Total days

5338

Weekend

482

Holidays

Holidays in the period

King's Birthday Mon 2 Jun 1975
Labour Day Mon 27 Oct 1975
Christmas Day Thu 25 Dec 1975
Boxing Day Fri 26 Dec 1975
New Year's Day Thu 1 Jan 1976
Day after New Year's Day Fri 2 Jan 1976
Waitangi Day Fri 6 Feb 1976
Good Friday Fri 16 Apr 1976
Easter Monday Mon 19 Apr 1976
Anzac Day Mon 26 Apr 1976
King's Birthday Mon 7 Jun 1976
Labour Day Mon 25 Oct 1976
Christmas Day Mon 27 Dec 1976
Boxing Day Mon 27 Dec 1976
New Year's Day Mon 3 Jan 1977
Day after New Year's Day Mon 3 Jan 1977
Waitangi Day Mon 7 Feb 1977
Good Friday Fri 8 Apr 1977
Easter Monday Mon 11 Apr 1977
Anzac Day Mon 25 Apr 1977
King's Birthday Mon 6 Jun 1977
Labour Day Mon 24 Oct 1977
Christmas Day Mon 26 Dec 1977
Boxing Day Mon 26 Dec 1977
New Year's Day Mon 2 Jan 1978
Day after New Year's Day Mon 2 Jan 1978
Waitangi Day Mon 6 Feb 1978
Good Friday Fri 24 Mar 1978
Easter Monday Mon 27 Mar 1978
Anzac Day Tue 25 Apr 1978
King's Birthday Mon 5 Jun 1978
Labour Day Mon 23 Oct 1978
Christmas Day Mon 25 Dec 1978
Boxing Day Tue 26 Dec 1978
New Year's Day Mon 1 Jan 1979
Day after New Year's Day Tue 2 Jan 1979
Waitangi Day Tue 6 Feb 1979
Good Friday Fri 13 Apr 1979
Easter Monday Mon 16 Apr 1979
Anzac Day Wed 25 Apr 1979
King's Birthday Mon 4 Jun 1979
Labour Day Mon 22 Oct 1979
Christmas Day Tue 25 Dec 1979
Boxing Day Wed 26 Dec 1979
New Year's Day Tue 1 Jan 1980
Day after New Year's Day Wed 2 Jan 1980
Waitangi Day Wed 6 Feb 1980
Good Friday Fri 4 Apr 1980
Easter Monday Mon 7 Apr 1980
Anzac Day Fri 25 Apr 1980
King's Birthday Mon 2 Jun 1980
Labour Day Mon 27 Oct 1980
Christmas Day Thu 25 Dec 1980
Boxing Day Fri 26 Dec 1980
New Year's Day Thu 1 Jan 1981
Day after New Year's Day Fri 2 Jan 1981
Waitangi Day Fri 6 Feb 1981
Good Friday Fri 17 Apr 1981
Easter Monday Mon 20 Apr 1981
Anzac Day Mon 27 Apr 1981
King's Birthday Mon 1 Jun 1981
Labour Day Mon 26 Oct 1981
Christmas Day Fri 25 Dec 1981
Boxing Day Mon 28 Dec 1981
New Year's Day Fri 1 Jan 1982
Day after New Year's Day Mon 4 Jan 1982
Waitangi Day Mon 8 Feb 1982
Good Friday Fri 9 Apr 1982
Easter Monday Mon 12 Apr 1982
Anzac Day Mon 26 Apr 1982
King's Birthday Mon 7 Jun 1982
Labour Day Mon 25 Oct 1982
Christmas Day Mon 27 Dec 1982
Boxing Day Mon 27 Dec 1982
New Year's Day Mon 3 Jan 1983
Day after New Year's Day Mon 3 Jan 1983
Waitangi Day Mon 7 Feb 1983
Good Friday Fri 1 Apr 1983
Easter Monday Mon 4 Apr 1983
Anzac Day Mon 25 Apr 1983
King's Birthday Mon 6 Jun 1983
Labour Day Mon 24 Oct 1983
Christmas Day Mon 26 Dec 1983
Boxing Day Mon 26 Dec 1983
New Year's Day Mon 2 Jan 1984
Day after New Year's Day Mon 2 Jan 1984
Waitangi Day Mon 6 Feb 1984
Good Friday Fri 20 Apr 1984
Easter Monday Mon 23 Apr 1984
Anzac Day Wed 25 Apr 1984
King's Birthday Mon 4 Jun 1984
Labour Day Mon 22 Oct 1984
Christmas Day Tue 25 Dec 1984
Boxing Day Wed 26 Dec 1984
New Year's Day Tue 1 Jan 1985
Day after New Year's Day Wed 2 Jan 1985
Waitangi Day Wed 6 Feb 1985
Good Friday Fri 5 Apr 1985
Easter Monday Mon 8 Apr 1985
Anzac Day Thu 25 Apr 1985
King's Birthday Mon 3 Jun 1985
Labour Day Mon 28 Oct 1985
Christmas Day Wed 25 Dec 1985
Boxing Day Thu 26 Dec 1985
New Year's Day Wed 1 Jan 1986
Day after New Year's Day Thu 2 Jan 1986
Waitangi Day Thu 6 Feb 1986
Good Friday Fri 28 Mar 1986
Easter Monday Mon 31 Mar 1986
Anzac Day Fri 25 Apr 1986
King's Birthday Mon 2 Jun 1986
Labour Day Mon 27 Oct 1986
Christmas Day Thu 25 Dec 1986
Boxing Day Fri 26 Dec 1986
New Year's Day Thu 1 Jan 1987
Day after New Year's Day Fri 2 Jan 1987
Waitangi Day Fri 6 Feb 1987
Good Friday Fri 17 Apr 1987
Easter Monday Mon 20 Apr 1987
Anzac Day Mon 27 Apr 1987
King's Birthday Mon 1 Jun 1987
Labour Day Mon 26 Oct 1987
Christmas Day Fri 25 Dec 1987
Boxing Day Mon 28 Dec 1987
New Year's Day Fri 1 Jan 1988
Day after New Year's Day Mon 4 Jan 1988
Waitangi Day Mon 8 Feb 1988
Good Friday Fri 1 Apr 1988
Easter Monday Mon 4 Apr 1988
Anzac Day Mon 25 Apr 1988
King's Birthday Mon 6 Jun 1988
Labour Day Mon 24 Oct 1988
Christmas Day Mon 26 Dec 1988
Boxing Day Mon 26 Dec 1988
New Year's Day Mon 2 Jan 1989
Day after New Year's Day Mon 2 Jan 1989
Waitangi Day Mon 6 Feb 1989
Good Friday Fri 24 Mar 1989
Easter Monday Mon 27 Mar 1989
Anzac Day Tue 25 Apr 1989
King's Birthday Mon 5 Jun 1989
Labour Day Mon 23 Oct 1989
Christmas Day Mon 25 Dec 1989
Boxing Day Tue 26 Dec 1989
New Year's Day Mon 1 Jan 1990
Day after New Year's Day Tue 2 Jan 1990
Waitangi Day Tue 6 Feb 1990
Good Friday Fri 13 Apr 1990
Easter Monday Mon 16 Apr 1990
Anzac Day Wed 25 Apr 1990
King's Birthday Mon 4 Jun 1990
Labour Day Mon 22 Oct 1990
Christmas Day Tue 25 Dec 1990
Boxing Day Wed 26 Dec 1990
New Year's Day Tue 1 Jan 1991
Day after New Year's Day Wed 2 Jan 1991
Waitangi Day Wed 6 Feb 1991
Good Friday Fri 29 Mar 1991
Easter Monday Mon 1 Apr 1991
Anzac Day Thu 25 Apr 1991
King's Birthday Mon 3 Jun 1991
Labour Day Mon 28 Oct 1991
Christmas Day Wed 25 Dec 1991
Boxing Day Thu 26 Dec 1991
New Year's Day Wed 1 Jan 1992
Day after New Year's Day Thu 2 Jan 1992
Waitangi Day Thu 6 Feb 1992
Good Friday Fri 17 Apr 1992
Easter Monday Mon 20 Apr 1992
Anzac Day Mon 27 Apr 1992
King's Birthday Mon 1 Jun 1992
Labour Day Mon 26 Oct 1992
Christmas Day Fri 25 Dec 1992
Boxing Day Mon 28 Dec 1992
New Year's Day Fri 1 Jan 1993
Day after New Year's Day Mon 4 Jan 1993
Waitangi Day Mon 8 Feb 1993
Good Friday Fri 9 Apr 1993
Easter Monday Mon 12 Apr 1993
Anzac Day Mon 26 Apr 1993
King's Birthday Mon 7 Jun 1993
Labour Day Mon 25 Oct 1993
Christmas Day Mon 27 Dec 1993
Boxing Day Mon 27 Dec 1993
New Year's Day Mon 3 Jan 1994
Day after New Year's Day Mon 3 Jan 1994
Waitangi Day Mon 7 Feb 1994
Good Friday Fri 1 Apr 1994
Easter Monday Mon 4 Apr 1994
Anzac Day Mon 25 Apr 1994
King's Birthday Mon 6 Jun 1994
Labour Day Mon 24 Oct 1994
Christmas Day Mon 26 Dec 1994
Boxing Day Mon 26 Dec 1994
New Year's Day Mon 2 Jan 1995
Day after New Year's Day Mon 2 Jan 1995
Waitangi Day Mon 6 Feb 1995
Good Friday Fri 14 Apr 1995
Easter Monday Mon 17 Apr 1995
Anzac Day Tue 25 Apr 1995
King's Birthday Mon 5 Jun 1995
Labour Day Mon 23 Oct 1995
Christmas Day Mon 25 Dec 1995
Boxing Day Tue 26 Dec 1995
New Year's Day Mon 1 Jan 1996
Day after New Year's Day Tue 2 Jan 1996
Waitangi Day Tue 6 Feb 1996
Good Friday Fri 5 Apr 1996
Easter Monday Mon 8 Apr 1996
Anzac Day Thu 25 Apr 1996
King's Birthday Mon 3 Jun 1996
Labour Day Mon 28 Oct 1996
Christmas Day Wed 25 Dec 1996
Boxing Day Thu 26 Dec 1996
New Year's Day Wed 1 Jan 1997
Day after New Year's Day Thu 2 Jan 1997
Waitangi Day Thu 6 Feb 1997
Good Friday Fri 28 Mar 1997
Easter Monday Mon 31 Mar 1997
Anzac Day Fri 25 Apr 1997
King's Birthday Mon 2 Jun 1997
Labour Day Mon 27 Oct 1997
Christmas Day Thu 25 Dec 1997
Boxing Day Fri 26 Dec 1997
New Year's Day Thu 1 Jan 1998
Day after New Year's Day Fri 2 Jan 1998
Waitangi Day Fri 6 Feb 1998
Good Friday Fri 10 Apr 1998
Easter Monday Mon 13 Apr 1998
Anzac Day Mon 27 Apr 1998
King's Birthday Mon 1 Jun 1998
Labour Day Mon 26 Oct 1998
Christmas Day Fri 25 Dec 1998
Boxing Day Mon 28 Dec 1998
New Year's Day Fri 1 Jan 1999
Day after New Year's Day Mon 4 Jan 1999
Waitangi Day Mon 8 Feb 1999
Good Friday Fri 2 Apr 1999
Easter Monday Mon 5 Apr 1999
Anzac Day Mon 26 Apr 1999
King's Birthday Mon 7 Jun 1999
Labour Day Mon 25 Oct 1999
Christmas Day Mon 27 Dec 1999
Boxing Day Mon 27 Dec 1999
New Year's Day Mon 3 Jan 2000
Day after New Year's Day Mon 3 Jan 2000
Waitangi Day Mon 7 Feb 2000
Good Friday Fri 21 Apr 2000
Easter Monday Mon 24 Apr 2000
Anzac Day Tue 25 Apr 2000
King's Birthday Mon 5 Jun 2000
Labour Day Mon 23 Oct 2000
Christmas Day Mon 25 Dec 2000
Boxing Day Tue 26 Dec 2000
New Year's Day Mon 1 Jan 2001
Day after New Year's Day Tue 2 Jan 2001
Waitangi Day Tue 6 Feb 2001
Good Friday Fri 13 Apr 2001
Easter Monday Mon 16 Apr 2001
Anzac Day Wed 25 Apr 2001
King's Birthday Mon 4 Jun 2001
Labour Day Mon 22 Oct 2001
Christmas Day Tue 25 Dec 2001
Boxing Day Wed 26 Dec 2001
New Year's Day Tue 1 Jan 2002
Day after New Year's Day Wed 2 Jan 2002
Waitangi Day Wed 6 Feb 2002
Good Friday Fri 29 Mar 2002
Easter Monday Mon 1 Apr 2002
Anzac Day Thu 25 Apr 2002
King's Birthday Mon 3 Jun 2002
Labour Day Mon 28 Oct 2002
Christmas Day Wed 25 Dec 2002
Boxing Day Thu 26 Dec 2002
New Year's Day Wed 1 Jan 2003
Day after New Year's Day Thu 2 Jan 2003
Waitangi Day Thu 6 Feb 2003
Good Friday Fri 18 Apr 2003
Easter Monday Mon 21 Apr 2003
Anzac Day Fri 25 Apr 2003
King's Birthday Mon 2 Jun 2003
Labour Day Mon 27 Oct 2003
Christmas Day Thu 25 Dec 2003
Boxing Day Fri 26 Dec 2003
New Year's Day Thu 1 Jan 2004
Day after New Year's Day Fri 2 Jan 2004
Waitangi Day Fri 6 Feb 2004
Good Friday Fri 9 Apr 2004
Easter Monday Mon 12 Apr 2004
Anzac Day Mon 26 Apr 2004
King's Birthday Mon 7 Jun 2004
Labour Day Mon 25 Oct 2004
Christmas Day Mon 27 Dec 2004
Boxing Day Mon 27 Dec 2004
New Year's Day Mon 3 Jan 2005
Day after New Year's Day Mon 3 Jan 2005
Waitangi Day Mon 7 Feb 2005
Good Friday Fri 25 Mar 2005
Easter Monday Mon 28 Mar 2005
Anzac Day Mon 25 Apr 2005
King's Birthday Mon 6 Jun 2005
Labour Day Mon 24 Oct 2005
Christmas Day Mon 26 Dec 2005
Boxing Day Mon 26 Dec 2005
New Year's Day Mon 2 Jan 2006
Day after New Year's Day Mon 2 Jan 2006
Waitangi Day Mon 6 Feb 2006
Good Friday Fri 14 Apr 2006
Easter Monday Mon 17 Apr 2006
Anzac Day Tue 25 Apr 2006
King's Birthday Mon 5 Jun 2006
Labour Day Mon 23 Oct 2006
Christmas Day Mon 25 Dec 2006
Boxing Day Tue 26 Dec 2006
New Year's Day Mon 1 Jan 2007
Day after New Year's Day Tue 2 Jan 2007
Waitangi Day Tue 6 Feb 2007
Good Friday Fri 6 Apr 2007
Easter Monday Mon 9 Apr 2007
Anzac Day Wed 25 Apr 2007
King's Birthday Mon 4 Jun 2007
Labour Day Mon 22 Oct 2007
Christmas Day Tue 25 Dec 2007
Boxing Day Wed 26 Dec 2007
New Year's Day Tue 1 Jan 2008
Day after New Year's Day Wed 2 Jan 2008
Waitangi Day Wed 6 Feb 2008
Good Friday Fri 21 Mar 2008
Easter Monday Mon 24 Mar 2008
Anzac Day Fri 25 Apr 2008
King's Birthday Mon 2 Jun 2008
Labour Day Mon 27 Oct 2008
Christmas Day Thu 25 Dec 2008
Boxing Day Fri 26 Dec 2008
New Year's Day Thu 1 Jan 2009
Day after New Year's Day Fri 2 Jan 2009
Waitangi Day Fri 6 Feb 2009
Good Friday Fri 10 Apr 2009
Easter Monday Mon 13 Apr 2009
Anzac Day Mon 27 Apr 2009
King's Birthday Mon 1 Jun 2009
Labour Day Mon 26 Oct 2009
Christmas Day Fri 25 Dec 2009
Boxing Day Mon 28 Dec 2009
New Year's Day Fri 1 Jan 2010
Day after New Year's Day Mon 4 Jan 2010
Waitangi Day Mon 8 Feb 2010
Good Friday Fri 2 Apr 2010
Easter Monday Mon 5 Apr 2010
Anzac Day Mon 26 Apr 2010
King's Birthday Mon 7 Jun 2010
Labour Day Mon 25 Oct 2010
Christmas Day Mon 27 Dec 2010
Boxing Day Mon 27 Dec 2010
New Year's Day Mon 3 Jan 2011
Day after New Year's Day Mon 3 Jan 2011
Waitangi Day Mon 7 Feb 2011
Good Friday Fri 22 Apr 2011
Anzac Day Mon 25 Apr 2011
Easter Monday Mon 25 Apr 2011
King's Birthday Mon 6 Jun 2011
Labour Day Mon 24 Oct 2011
Christmas Day Mon 26 Dec 2011
Boxing Day Mon 26 Dec 2011
New Year's Day Mon 2 Jan 2012
Day after New Year's Day Mon 2 Jan 2012
Waitangi Day Mon 6 Feb 2012
Good Friday Fri 6 Apr 2012
Easter Monday Mon 9 Apr 2012
Anzac Day Wed 25 Apr 2012
King's Birthday Mon 4 Jun 2012
Labour Day Mon 22 Oct 2012
Christmas Day Tue 25 Dec 2012
Boxing Day Wed 26 Dec 2012
New Year's Day Tue 1 Jan 2013
Day after New Year's Day Wed 2 Jan 2013
Waitangi Day Wed 6 Feb 2013
Good Friday Fri 29 Mar 2013
Easter Monday Mon 1 Apr 2013
Anzac Day Thu 25 Apr 2013
King's Birthday Mon 3 Jun 2013
Labour Day Mon 28 Oct 2013
Christmas Day Wed 25 Dec 2013
Boxing Day Thu 26 Dec 2013
New Year's Day Wed 1 Jan 2014
Day after New Year's Day Thu 2 Jan 2014
Waitangi Day Thu 6 Feb 2014
Good Friday Fri 18 Apr 2014
Easter Monday Mon 21 Apr 2014
Anzac Day Fri 25 Apr 2014
King's Birthday Mon 2 Jun 2014
Labour Day Mon 27 Oct 2014
Christmas Day Thu 25 Dec 2014
Boxing Day Fri 26 Dec 2014
New Year's Day Thu 1 Jan 2015
Day after New Year's Day Fri 2 Jan 2015
Waitangi Day Fri 6 Feb 2015
Good Friday Fri 3 Apr 2015
Easter Monday Mon 6 Apr 2015
Anzac Day Mon 27 Apr 2015
King's Birthday Mon 1 Jun 2015
Labour Day Mon 26 Oct 2015
Christmas Day Fri 25 Dec 2015
Boxing Day Mon 28 Dec 2015
New Year's Day Fri 1 Jan 2016
Day after New Year's Day Mon 4 Jan 2016
Waitangi Day Mon 8 Feb 2016
Good Friday Fri 25 Mar 2016
Easter Monday Mon 28 Mar 2016
Anzac Day Mon 25 Apr 2016
King's Birthday Mon 6 Jun 2016
Labour Day Mon 24 Oct 2016
Christmas Day Mon 26 Dec 2016
Boxing Day Mon 26 Dec 2016
New Year's Day Mon 2 Jan 2017
Day after New Year's Day Mon 2 Jan 2017
Waitangi Day Mon 6 Feb 2017
Good Friday Fri 14 Apr 2017
Easter Monday Mon 17 Apr 2017
Anzac Day Tue 25 Apr 2017
King's Birthday Mon 5 Jun 2017
Labour Day Mon 23 Oct 2017
Christmas Day Mon 25 Dec 2017
Boxing Day Tue 26 Dec 2017
New Year's Day Mon 1 Jan 2018
Day after New Year's Day Tue 2 Jan 2018
Waitangi Day Tue 6 Feb 2018
Good Friday Fri 30 Mar 2018
Easter Monday Mon 2 Apr 2018
Anzac Day Wed 25 Apr 2018
King's Birthday Mon 4 Jun 2018
Labour Day Mon 22 Oct 2018
Christmas Day Tue 25 Dec 2018
Boxing Day Wed 26 Dec 2018
New Year's Day Tue 1 Jan 2019
Day after New Year's Day Wed 2 Jan 2019
Waitangi Day Wed 6 Feb 2019
Good Friday Fri 19 Apr 2019
Easter Monday Mon 22 Apr 2019
Anzac Day Thu 25 Apr 2019
King's Birthday Mon 3 Jun 2019
Labour Day Mon 28 Oct 2019
Christmas Day Wed 25 Dec 2019
Boxing Day Thu 26 Dec 2019
New Year's Day Wed 1 Jan 2020
Day after New Year's Day Thu 2 Jan 2020
Waitangi Day Thu 6 Feb 2020
Good Friday Fri 10 Apr 2020
Easter Monday Mon 13 Apr 2020
Anzac Day Mon 27 Apr 2020
King's Birthday Mon 1 Jun 2020
Labour Day Mon 26 Oct 2020
Christmas Day Fri 25 Dec 2020
Boxing Day Mon 28 Dec 2020
New Year's Day Fri 1 Jan 2021
Day after New Year's Day Mon 4 Jan 2021
Waitangi Day Mon 8 Feb 2021
Good Friday Fri 2 Apr 2021
Easter Monday Mon 5 Apr 2021
Anzac Day Mon 26 Apr 2021
King's Birthday Mon 7 Jun 2021
Labour Day Mon 25 Oct 2021
Christmas Day Mon 27 Dec 2021
Boxing Day Mon 27 Dec 2021
New Year's Day Mon 3 Jan 2022
Day after New Year's Day Mon 3 Jan 2022
Waitangi Day Mon 7 Feb 2022
Good Friday Fri 15 Apr 2022
Easter Monday Mon 18 Apr 2022
Anzac Day Mon 25 Apr 2022
King's Birthday Mon 6 Jun 2022
Labour Day Mon 24 Oct 2022
Christmas Day Mon 26 Dec 2022
Boxing Day Mon 26 Dec 2022
New Year's Day Mon 2 Jan 2023
Day after New Year's Day Mon 2 Jan 2023
Waitangi Day Mon 6 Feb 2023
Good Friday Fri 7 Apr 2023
Easter Monday Mon 10 Apr 2023
Anzac Day Tue 25 Apr 2023
King's Birthday Mon 5 Jun 2023
Labour Day Mon 23 Oct 2023
Christmas Day Mon 25 Dec 2023
Boxing Day Tue 26 Dec 2023
New Year's Day Mon 1 Jan 2024
Day after New Year's Day Tue 2 Jan 2024
Waitangi Day Tue 6 Feb 2024
Good Friday Fri 29 Mar 2024
Easter Monday Mon 1 Apr 2024
Anzac Day Thu 25 Apr 2024
King's Birthday Mon 3 Jun 2024
Labour Day Mon 28 Oct 2024
Christmas Day Wed 25 Dec 2024
Boxing Day Thu 26 Dec 2024
New Year's Day Wed 1 Jan 2025
Day after New Year's Day Thu 2 Jan 2025
Waitangi Day Thu 6 Feb 2025
Good Friday Fri 18 Apr 2025
Easter Monday Mon 21 Apr 2025
Anzac Day Fri 25 Apr 2025
King's Birthday Mon 2 Jun 2025
Matariki Fri 20 Jun 2025
Labour Day Mon 27 Oct 2025
Christmas Day Thu 25 Dec 2025
Boxing Day Fri 26 Dec 2025
New Year's Day Thu 1 Jan 2026
Day after New Year's Day Fri 2 Jan 2026
Waitangi Day Fri 6 Feb 2026
Good Friday Fri 3 Apr 2026
Easter Monday Mon 6 Apr 2026
Anzac Day Mon 27 Apr 2026
King's Birthday Mon 1 Jun 2026
Matariki Fri 10 Jul 2026

Preguntas frecuentes

What counts as a business day?

In CivicCalendar a business day is a Monday–Friday that is not a legal holiday in New Zealand. Saturdays and Sundays are not counted.

Is the start day included?

Yes. In “Between two dates” mode both dates are inclusive. In “Add business days”, counting starts on the start date if that date is a business day.

Are regional holidays considered?

National holidays and regional holidays defined for the country are used. If a regional holiday does not apply to your area, the result may differ.

Is this an official calculation?

It is indicative according to current legislation and calendars loaded on the site. For critical legal or labor deadlines, confirm with the relevant rule or authority.