Chile

Business days calculator

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

Between two dates Add business days

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

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

6442

business days

From July 23, 2026 to July 1, 2052

Business day 6442
Weekend 2708
Holidays 325

9476 days in the period

9476

Total days

2708

Weekend

325

Holidays

Holidays in the period

Assumption Sat 15 Aug 2026
O'Higgins' Birthday Thu 20 Aug 2026
Independence Day Fri 18 Sep 2026
Army Day Sat 19 Sep 2026
Encounter of Two Worlds Mon 12 Oct 2026
Protestant Churches Day Sat 31 Oct 2026
All Saints' Day Sun 1 Nov 2026
Immaculate Conception Tue 8 Dec 2026
Christmas Fri 25 Dec 2026
New Year's Day Fri 1 Jan 2027
Good Friday Fri 26 Mar 2027
Holy Saturday Sat 27 Mar 2027
Easter Sunday Sun 28 Mar 2027
Labor Day Sat 1 May 2027
Navy Day Fri 21 May 2027
Battle of Arica Day Mon 7 Jun 2027
Indigenous Peoples' Day Mon 21 Jun 2027
Saints Peter and Paul Tue 29 Jun 2027
Our Lady of Mount Carmel Fri 16 Jul 2027
Assumption Sun 15 Aug 2027
O'Higgins' Birthday Fri 20 Aug 2027
Independence Day Sat 18 Sep 2027
Army Day Sun 19 Sep 2027
Encounter of Two Worlds Tue 12 Oct 2027
Protestant Churches Day Sun 31 Oct 2027
All Saints' Day Mon 1 Nov 2027
Immaculate Conception Wed 8 Dec 2027
Christmas Sat 25 Dec 2027
New Year's Day Sat 1 Jan 2028
Good Friday Fri 14 Apr 2028
Holy Saturday Sat 15 Apr 2028
Easter Sunday Sun 16 Apr 2028
Labor Day Mon 1 May 2028
Navy Day Sun 21 May 2028
Battle of Arica Day Wed 7 Jun 2028
Indigenous Peoples' Day Wed 21 Jun 2028
Saints Peter and Paul Thu 29 Jun 2028
Our Lady of Mount Carmel Sun 16 Jul 2028
Assumption Tue 15 Aug 2028
O'Higgins' Birthday Sun 20 Aug 2028
Independence Day Mon 18 Sep 2028
Army Day Tue 19 Sep 2028
Encounter of Two Worlds Thu 12 Oct 2028
Protestant Churches Day Tue 31 Oct 2028
All Saints' Day Wed 1 Nov 2028
Immaculate Conception Fri 8 Dec 2028
Christmas Mon 25 Dec 2028
New Year's Day Mon 1 Jan 2029
Good Friday Fri 30 Mar 2029
Holy Saturday Sat 31 Mar 2029
Easter Sunday Sun 1 Apr 2029
Labor Day Tue 1 May 2029
Navy Day Mon 21 May 2029
Battle of Arica Day Thu 7 Jun 2029
Indigenous Peoples' Day Thu 21 Jun 2029
Saints Peter and Paul Fri 29 Jun 2029
Our Lady of Mount Carmel Mon 16 Jul 2029
Assumption Wed 15 Aug 2029
O'Higgins' Birthday Mon 20 Aug 2029
Independence Day Tue 18 Sep 2029
Army Day Wed 19 Sep 2029
Encounter of Two Worlds Fri 12 Oct 2029
Protestant Churches Day Wed 31 Oct 2029
All Saints' Day Thu 1 Nov 2029
Immaculate Conception Sat 8 Dec 2029
Christmas Tue 25 Dec 2029
New Year's Day Tue 1 Jan 2030
Good Friday Fri 19 Apr 2030
Holy Saturday Sat 20 Apr 2030
Easter Sunday Sun 21 Apr 2030
Labor Day Wed 1 May 2030
Navy Day Tue 21 May 2030
Battle of Arica Day Fri 7 Jun 2030
Indigenous Peoples' Day Fri 21 Jun 2030
Saints Peter and Paul Mon 1 Jul 2030
Our Lady of Mount Carmel Tue 16 Jul 2030
Assumption Thu 15 Aug 2030
O'Higgins' Birthday Tue 20 Aug 2030
Independence Day Wed 18 Sep 2030
Army Day Thu 19 Sep 2030
Encounter of Two Worlds Sat 12 Oct 2030
Protestant Churches Day Thu 31 Oct 2030
All Saints' Day Fri 1 Nov 2030
Immaculate Conception Sun 8 Dec 2030
Christmas Wed 25 Dec 2030
New Year's Day Wed 1 Jan 2031
Good Friday Fri 11 Apr 2031
Holy Saturday Sat 12 Apr 2031
Easter Sunday Sun 13 Apr 2031
Labor Day Thu 1 May 2031
Navy Day Wed 21 May 2031
Battle of Arica Day Sat 7 Jun 2031
Indigenous Peoples' Day Sat 21 Jun 2031
Saints Peter and Paul Sun 29 Jun 2031
Our Lady of Mount Carmel Wed 16 Jul 2031
Assumption Fri 15 Aug 2031
O'Higgins' Birthday Wed 20 Aug 2031
Independence Day Thu 18 Sep 2031
Army Day Fri 19 Sep 2031
Encounter of Two Worlds Sun 12 Oct 2031
Protestant Churches Day Fri 31 Oct 2031
All Saints' Day Sat 1 Nov 2031
Immaculate Conception Mon 8 Dec 2031
Christmas Thu 25 Dec 2031
New Year's Day Thu 1 Jan 2032
Good Friday Fri 26 Mar 2032
Holy Saturday Sat 27 Mar 2032
Easter Sunday Sun 28 Mar 2032
Labor Day Sat 1 May 2032
Navy Day Fri 21 May 2032
Battle of Arica Day Mon 7 Jun 2032
Indigenous Peoples' Day Mon 21 Jun 2032
Saints Peter and Paul Tue 29 Jun 2032
Our Lady of Mount Carmel Fri 16 Jul 2032
Assumption Sun 15 Aug 2032
O'Higgins' Birthday Fri 20 Aug 2032
Independence Day Sat 18 Sep 2032
Army Day Sun 19 Sep 2032
Encounter of Two Worlds Tue 12 Oct 2032
Protestant Churches Day Sun 31 Oct 2032
All Saints' Day Mon 1 Nov 2032
Immaculate Conception Wed 8 Dec 2032
Christmas Sat 25 Dec 2032
New Year's Day Sat 1 Jan 2033
Good Friday Fri 15 Apr 2033
Holy Saturday Sat 16 Apr 2033
Easter Sunday Sun 17 Apr 2033
Labor Day Sun 1 May 2033
Navy Day Sat 21 May 2033
Battle of Arica Day Tue 7 Jun 2033
Indigenous Peoples' Day Tue 21 Jun 2033
Saints Peter and Paul Wed 29 Jun 2033
Our Lady of Mount Carmel Sat 16 Jul 2033
Assumption Mon 15 Aug 2033
O'Higgins' Birthday Sat 20 Aug 2033
Independence Day Sun 18 Sep 2033
Army Day Mon 19 Sep 2033
Encounter of Two Worlds Wed 12 Oct 2033
Protestant Churches Day Mon 31 Oct 2033
All Saints' Day Tue 1 Nov 2033
Immaculate Conception Thu 8 Dec 2033
Christmas Sun 25 Dec 2033
New Year's Day Sun 1 Jan 2034
Good Friday Fri 7 Apr 2034
Holy Saturday Sat 8 Apr 2034
Easter Sunday Sun 9 Apr 2034
Labor Day Mon 1 May 2034
Navy Day Sun 21 May 2034
Battle of Arica Day Wed 7 Jun 2034
Indigenous Peoples' Day Wed 21 Jun 2034
Saints Peter and Paul Thu 29 Jun 2034
Our Lady of Mount Carmel Sun 16 Jul 2034
Assumption Tue 15 Aug 2034
O'Higgins' Birthday Sun 20 Aug 2034
Independence Day Mon 18 Sep 2034
Army Day Tue 19 Sep 2034
Encounter of Two Worlds Thu 12 Oct 2034
Protestant Churches Day Tue 31 Oct 2034
All Saints' Day Wed 1 Nov 2034
Immaculate Conception Fri 8 Dec 2034
Christmas Mon 25 Dec 2034
New Year's Day Mon 1 Jan 2035
Good Friday Fri 23 Mar 2035
Holy Saturday Sat 24 Mar 2035
Easter Sunday Sun 25 Mar 2035
Labor Day Tue 1 May 2035
Navy Day Mon 21 May 2035
Battle of Arica Day Thu 7 Jun 2035
Indigenous Peoples' Day Thu 21 Jun 2035
Saints Peter and Paul Fri 29 Jun 2035
Our Lady of Mount Carmel Mon 16 Jul 2035
Assumption Wed 15 Aug 2035
O'Higgins' Birthday Mon 20 Aug 2035
Independence Day Tue 18 Sep 2035
Army Day Wed 19 Sep 2035
Encounter of Two Worlds Fri 12 Oct 2035
Protestant Churches Day Wed 31 Oct 2035
All Saints' Day Thu 1 Nov 2035
Immaculate Conception Sat 8 Dec 2035
Christmas Tue 25 Dec 2035
New Year's Day Tue 1 Jan 2036
Good Friday Fri 11 Apr 2036
Holy Saturday Sat 12 Apr 2036
Easter Sunday Sun 13 Apr 2036
Labor Day Thu 1 May 2036
Navy Day Wed 21 May 2036
Battle of Arica Day Sat 7 Jun 2036
Indigenous Peoples' Day Sat 21 Jun 2036
Saints Peter and Paul Sun 29 Jun 2036
Our Lady of Mount Carmel Wed 16 Jul 2036
Assumption Fri 15 Aug 2036
O'Higgins' Birthday Wed 20 Aug 2036
Independence Day Thu 18 Sep 2036
Army Day Fri 19 Sep 2036
Encounter of Two Worlds Sun 12 Oct 2036
Protestant Churches Day Fri 31 Oct 2036
All Saints' Day Sat 1 Nov 2036
Immaculate Conception Mon 8 Dec 2036
Christmas Thu 25 Dec 2036
New Year's Day Thu 1 Jan 2037
Good Friday Fri 3 Apr 2037
Holy Saturday Sat 4 Apr 2037
Easter Sunday Sun 5 Apr 2037
Labor Day Fri 1 May 2037
Navy Day Thu 21 May 2037
Battle of Arica Day Sun 7 Jun 2037
Indigenous Peoples' Day Sun 21 Jun 2037
Saints Peter and Paul Mon 29 Jun 2037
Our Lady of Mount Carmel Thu 16 Jul 2037
Assumption Sat 15 Aug 2037
O'Higgins' Birthday Thu 20 Aug 2037
Independence Day Fri 18 Sep 2037
Army Day Sat 19 Sep 2037
Encounter of Two Worlds Mon 12 Oct 2037
Protestant Churches Day Sat 31 Oct 2037
All Saints' Day Sun 1 Nov 2037
Immaculate Conception Tue 8 Dec 2037
Christmas Fri 25 Dec 2037
New Year's Day Fri 1 Jan 2038
Good Friday Fri 23 Apr 2038
Holy Saturday Sat 24 Apr 2038
Easter Sunday Sun 25 Apr 2038
Labor Day Sat 1 May 2038
Navy Day Fri 21 May 2038
Battle of Arica Day Mon 7 Jun 2038
Indigenous Peoples' Day Mon 21 Jun 2038
Saints Peter and Paul Tue 29 Jun 2038
Our Lady of Mount Carmel Fri 16 Jul 2038
Assumption Sun 15 Aug 2038
O'Higgins' Birthday Fri 20 Aug 2038
Independence Day Sat 18 Sep 2038
Army Day Sun 19 Sep 2038
Encounter of Two Worlds Tue 12 Oct 2038
Protestant Churches Day Sun 31 Oct 2038
All Saints' Day Mon 1 Nov 2038
Immaculate Conception Wed 8 Dec 2038
Christmas Sat 25 Dec 2038
New Year's Day Sat 1 Jan 2039
Good Friday Fri 8 Apr 2039
Holy Saturday Sat 9 Apr 2039
Easter Sunday Sun 10 Apr 2039
Labor Day Sun 1 May 2039
Navy Day Sat 21 May 2039
Battle of Arica Day Tue 7 Jun 2039
Indigenous Peoples' Day Tue 21 Jun 2039
Saints Peter and Paul Wed 29 Jun 2039
Our Lady of Mount Carmel Sat 16 Jul 2039
Assumption Mon 15 Aug 2039
O'Higgins' Birthday Sat 20 Aug 2039
Independence Day Sun 18 Sep 2039
Army Day Mon 19 Sep 2039
Encounter of Two Worlds Wed 12 Oct 2039
Protestant Churches Day Mon 31 Oct 2039
All Saints' Day Tue 1 Nov 2039
Immaculate Conception Thu 8 Dec 2039
Christmas Sun 25 Dec 2039
New Year's Day Sun 1 Jan 2040
Good Friday Fri 30 Mar 2040
Holy Saturday Sat 31 Mar 2040
Easter Sunday Sun 1 Apr 2040
Labor Day Tue 1 May 2040
Navy Day Mon 21 May 2040
Battle of Arica Day Thu 7 Jun 2040
Indigenous Peoples' Day Thu 21 Jun 2040
Saints Peter and Paul Fri 29 Jun 2040
Our Lady of Mount Carmel Mon 16 Jul 2040
Assumption Wed 15 Aug 2040
O'Higgins' Birthday Mon 20 Aug 2040
Independence Day Tue 18 Sep 2040
Army Day Wed 19 Sep 2040
Encounter of Two Worlds Fri 12 Oct 2040
Protestant Churches Day Wed 31 Oct 2040
All Saints' Day Thu 1 Nov 2040
Immaculate Conception Sat 8 Dec 2040
Christmas Tue 25 Dec 2040
New Year's Day Tue 1 Jan 2041
Good Friday Fri 19 Apr 2041
Holy Saturday Sat 20 Apr 2041
Easter Sunday Sun 21 Apr 2041
Labor Day Wed 1 May 2041
Navy Day Tue 21 May 2041
Battle of Arica Day Fri 7 Jun 2041
Indigenous Peoples' Day Fri 21 Jun 2041
Saints Peter and Paul Mon 1 Jul 2041
Our Lady of Mount Carmel Tue 16 Jul 2041
Assumption Thu 15 Aug 2041
O'Higgins' Birthday Tue 20 Aug 2041
Independence Day Wed 18 Sep 2041
Army Day Thu 19 Sep 2041
Encounter of Two Worlds Sat 12 Oct 2041
Protestant Churches Day Thu 31 Oct 2041
All Saints' Day Fri 1 Nov 2041
Immaculate Conception Sun 8 Dec 2041
Christmas Wed 25 Dec 2041
New Year's Day Wed 1 Jan 2042
Good Friday Fri 4 Apr 2042
Holy Saturday Sat 5 Apr 2042
Easter Sunday Sun 6 Apr 2042
Labor Day Thu 1 May 2042
Navy Day Wed 21 May 2042
Battle of Arica Day Sat 7 Jun 2042
Indigenous Peoples' Day Sat 21 Jun 2042
Saints Peter and Paul Sun 29 Jun 2042
Our Lady of Mount Carmel Wed 16 Jul 2042
Assumption Fri 15 Aug 2042
O'Higgins' Birthday Wed 20 Aug 2042
Independence Day Thu 18 Sep 2042
Army Day Fri 19 Sep 2042
Encounter of Two Worlds Sun 12 Oct 2042
Protestant Churches Day Fri 31 Oct 2042
All Saints' Day Sat 1 Nov 2042
Immaculate Conception Mon 8 Dec 2042
Christmas Thu 25 Dec 2042
New Year's Day Thu 1 Jan 2043
Good Friday Fri 27 Mar 2043
Holy Saturday Sat 28 Mar 2043
Easter Sunday Sun 29 Mar 2043
Labor Day Fri 1 May 2043
Navy Day Thu 21 May 2043
Battle of Arica Day Sun 7 Jun 2043
Indigenous Peoples' Day Sun 21 Jun 2043
Saints Peter and Paul Mon 29 Jun 2043
Our Lady of Mount Carmel Thu 16 Jul 2043
Assumption Sat 15 Aug 2043
O'Higgins' Birthday Thu 20 Aug 2043
Independence Day Fri 18 Sep 2043
Army Day Sat 19 Sep 2043
Encounter of Two Worlds Mon 12 Oct 2043
Protestant Churches Day Sat 31 Oct 2043
All Saints' Day Sun 1 Nov 2043
Immaculate Conception Tue 8 Dec 2043
Christmas Fri 25 Dec 2043
New Year's Day Fri 1 Jan 2044
Good Friday Fri 15 Apr 2044
Holy Saturday Sat 16 Apr 2044
Easter Sunday Sun 17 Apr 2044
Labor Day Sun 1 May 2044
Navy Day Sat 21 May 2044
Battle of Arica Day Tue 7 Jun 2044
Indigenous Peoples' Day Tue 21 Jun 2044
Saints Peter and Paul Wed 29 Jun 2044
Our Lady of Mount Carmel Sat 16 Jul 2044
Assumption Mon 15 Aug 2044
O'Higgins' Birthday Sat 20 Aug 2044
Independence Day Sun 18 Sep 2044
Army Day Mon 19 Sep 2044
Encounter of Two Worlds Wed 12 Oct 2044
Protestant Churches Day Mon 31 Oct 2044
All Saints' Day Tue 1 Nov 2044
Immaculate Conception Thu 8 Dec 2044
Christmas Sun 25 Dec 2044
New Year's Day Sun 1 Jan 2045
Good Friday Fri 7 Apr 2045
Holy Saturday Sat 8 Apr 2045
Easter Sunday Sun 9 Apr 2045
Labor Day Mon 1 May 2045
Navy Day Sun 21 May 2045
Battle of Arica Day Wed 7 Jun 2045
Indigenous Peoples' Day Wed 21 Jun 2045
Saints Peter and Paul Thu 29 Jun 2045
Our Lady of Mount Carmel Sun 16 Jul 2045
Assumption Tue 15 Aug 2045
O'Higgins' Birthday Sun 20 Aug 2045
Independence Day Mon 18 Sep 2045
Army Day Tue 19 Sep 2045
Encounter of Two Worlds Thu 12 Oct 2045
Protestant Churches Day Tue 31 Oct 2045
All Saints' Day Wed 1 Nov 2045
Immaculate Conception Fri 8 Dec 2045
Christmas Mon 25 Dec 2045
New Year's Day Mon 1 Jan 2046
Good Friday Fri 23 Mar 2046
Holy Saturday Sat 24 Mar 2046
Easter Sunday Sun 25 Mar 2046
Labor Day Tue 1 May 2046
Navy Day Mon 21 May 2046
Battle of Arica Day Thu 7 Jun 2046
Indigenous Peoples' Day Thu 21 Jun 2046
Saints Peter and Paul Fri 29 Jun 2046
Our Lady of Mount Carmel Mon 16 Jul 2046
Assumption Wed 15 Aug 2046
O'Higgins' Birthday Mon 20 Aug 2046
Independence Day Tue 18 Sep 2046
Army Day Wed 19 Sep 2046
Encounter of Two Worlds Fri 12 Oct 2046
Protestant Churches Day Wed 31 Oct 2046
All Saints' Day Thu 1 Nov 2046
Immaculate Conception Sat 8 Dec 2046
Christmas Tue 25 Dec 2046
New Year's Day Tue 1 Jan 2047
Good Friday Fri 12 Apr 2047
Holy Saturday Sat 13 Apr 2047
Easter Sunday Sun 14 Apr 2047
Labor Day Wed 1 May 2047
Navy Day Tue 21 May 2047
Battle of Arica Day Fri 7 Jun 2047
Indigenous Peoples' Day Fri 21 Jun 2047
Saints Peter and Paul Mon 1 Jul 2047
Our Lady of Mount Carmel Tue 16 Jul 2047
Assumption Thu 15 Aug 2047
O'Higgins' Birthday Tue 20 Aug 2047
Independence Day Wed 18 Sep 2047
Army Day Thu 19 Sep 2047
Encounter of Two Worlds Sat 12 Oct 2047
Protestant Churches Day Thu 31 Oct 2047
All Saints' Day Fri 1 Nov 2047
Immaculate Conception Sun 8 Dec 2047
Christmas Wed 25 Dec 2047
New Year's Day Wed 1 Jan 2048
Good Friday Fri 3 Apr 2048
Holy Saturday Sat 4 Apr 2048
Easter Sunday Sun 5 Apr 2048
Labor Day Fri 1 May 2048
Navy Day Thu 21 May 2048
Battle of Arica Day Sun 7 Jun 2048
Indigenous Peoples' Day Sun 21 Jun 2048
Saints Peter and Paul Mon 29 Jun 2048
Our Lady of Mount Carmel Thu 16 Jul 2048
Assumption Sat 15 Aug 2048
O'Higgins' Birthday Thu 20 Aug 2048
Independence Day Fri 18 Sep 2048
Army Day Sat 19 Sep 2048
Encounter of Two Worlds Mon 12 Oct 2048
Protestant Churches Day Sat 31 Oct 2048
All Saints' Day Sun 1 Nov 2048
Immaculate Conception Tue 8 Dec 2048
Christmas Fri 25 Dec 2048
New Year's Day Fri 1 Jan 2049
Good Friday Fri 16 Apr 2049
Holy Saturday Sat 17 Apr 2049
Easter Sunday Sun 18 Apr 2049
Labor Day Sat 1 May 2049
Navy Day Fri 21 May 2049
Battle of Arica Day Mon 7 Jun 2049
Indigenous Peoples' Day Mon 21 Jun 2049
Saints Peter and Paul Tue 29 Jun 2049
Our Lady of Mount Carmel Fri 16 Jul 2049
Assumption Sun 15 Aug 2049
O'Higgins' Birthday Fri 20 Aug 2049
Independence Day Sat 18 Sep 2049
Army Day Sun 19 Sep 2049
Encounter of Two Worlds Tue 12 Oct 2049
Protestant Churches Day Sun 31 Oct 2049
All Saints' Day Mon 1 Nov 2049
Immaculate Conception Wed 8 Dec 2049
Christmas Sat 25 Dec 2049
New Year's Day Sat 1 Jan 2050
Good Friday Fri 8 Apr 2050
Holy Saturday Sat 9 Apr 2050
Easter Sunday Sun 10 Apr 2050
Labor Day Sun 1 May 2050
Navy Day Sat 21 May 2050
Battle of Arica Day Tue 7 Jun 2050
Indigenous Peoples' Day Tue 21 Jun 2050
Saints Peter and Paul Wed 29 Jun 2050
Our Lady of Mount Carmel Sat 16 Jul 2050
Assumption Mon 15 Aug 2050
O'Higgins' Birthday Sat 20 Aug 2050
Independence Day Sun 18 Sep 2050
Army Day Mon 19 Sep 2050
Encounter of Two Worlds Wed 12 Oct 2050
Protestant Churches Day Mon 31 Oct 2050
All Saints' Day Tue 1 Nov 2050
Immaculate Conception Thu 8 Dec 2050
Christmas Sun 25 Dec 2050
New Year's Day Sun 1 Jan 2051
Good Friday Fri 31 Mar 2051
Holy Saturday Sat 1 Apr 2051
Easter Sunday Sun 2 Apr 2051
Labor Day Mon 1 May 2051
Navy Day Sun 21 May 2051
Battle of Arica Day Wed 7 Jun 2051
Indigenous Peoples' Day Wed 21 Jun 2051
Saints Peter and Paul Thu 29 Jun 2051
Our Lady of Mount Carmel Sun 16 Jul 2051
Assumption Tue 15 Aug 2051
O'Higgins' Birthday Sun 20 Aug 2051
Independence Day Mon 18 Sep 2051
Army Day Tue 19 Sep 2051
Encounter of Two Worlds Thu 12 Oct 2051
Protestant Churches Day Tue 31 Oct 2051
All Saints' Day Wed 1 Nov 2051
Immaculate Conception Fri 8 Dec 2051
Christmas Mon 25 Dec 2051
New Year's Day Mon 1 Jan 2052
Good Friday Fri 19 Apr 2052
Holy Saturday Sat 20 Apr 2052
Easter Sunday Sun 21 Apr 2052
Labor Day Wed 1 May 2052
Navy Day Tue 21 May 2052
Battle of Arica Day Fri 7 Jun 2052
Indigenous Peoples' Day Fri 21 Jun 2052
Saints Peter and Paul Mon 1 Jul 2052

Preguntas frecuentes

What counts as a business day?

In CivicCalendar a business day is a Monday–Friday that is not a legal holiday in Chile. 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.