Perú

Business days calculator

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

Between two dates Add business days

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

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

7534

business days

From July 23, 2026 to November 1, 2056

Business day 7534
Weekend 3160
Holidays 366

11060 days in the period

11060

Total days

3160

Weekend

366

Holidays

Holidays in the period

Air Force Day Thu 23 Jul 2026
Independence Day Tue 28 Jul 2026
Independence Day (2nd) Wed 29 Jul 2026
Battle of Junín Thu 6 Aug 2026
Saint Rose of Lima Sun 30 Aug 2026
Battle of Angamos Thu 8 Oct 2026
All Saints' Day Sun 1 Nov 2026
Immaculate Conception Tue 8 Dec 2026
Battle of Ayacucho Wed 9 Dec 2026
Christmas Fri 25 Dec 2026
New Year's Day Fri 1 Jan 2027
Maundy Thursday Thu 25 Mar 2027
Good Friday Fri 26 Mar 2027
Labor Day Sat 1 May 2027
Battle of Arica / Flag Day Mon 7 Jun 2027
Saints Peter and Paul Tue 29 Jun 2027
Air Force Day Fri 23 Jul 2027
Independence Day Wed 28 Jul 2027
Independence Day (2nd) Thu 29 Jul 2027
Battle of Junín Fri 6 Aug 2027
Saint Rose of Lima Mon 30 Aug 2027
Battle of Angamos Fri 8 Oct 2027
All Saints' Day Mon 1 Nov 2027
Immaculate Conception Wed 8 Dec 2027
Battle of Ayacucho Thu 9 Dec 2027
Christmas Sat 25 Dec 2027
New Year's Day Sat 1 Jan 2028
Maundy Thursday Thu 13 Apr 2028
Good Friday Fri 14 Apr 2028
Labor Day Mon 1 May 2028
Battle of Arica / Flag Day Wed 7 Jun 2028
Saints Peter and Paul Thu 29 Jun 2028
Air Force Day Sun 23 Jul 2028
Independence Day Fri 28 Jul 2028
Independence Day (2nd) Sat 29 Jul 2028
Battle of Junín Sun 6 Aug 2028
Saint Rose of Lima Wed 30 Aug 2028
Battle of Angamos Sun 8 Oct 2028
All Saints' Day Wed 1 Nov 2028
Immaculate Conception Fri 8 Dec 2028
Battle of Ayacucho Sat 9 Dec 2028
Christmas Mon 25 Dec 2028
New Year's Day Mon 1 Jan 2029
Maundy Thursday Thu 29 Mar 2029
Good Friday Fri 30 Mar 2029
Labor Day Tue 1 May 2029
Battle of Arica / Flag Day Thu 7 Jun 2029
Saints Peter and Paul Fri 29 Jun 2029
Air Force Day Mon 23 Jul 2029
Independence Day Sat 28 Jul 2029
Independence Day (2nd) Sun 29 Jul 2029
Battle of Junín Mon 6 Aug 2029
Saint Rose of Lima Thu 30 Aug 2029
Battle of Angamos Mon 8 Oct 2029
All Saints' Day Thu 1 Nov 2029
Immaculate Conception Sat 8 Dec 2029
Battle of Ayacucho Sun 9 Dec 2029
Christmas Tue 25 Dec 2029
New Year's Day Tue 1 Jan 2030
Maundy Thursday Thu 18 Apr 2030
Good Friday Fri 19 Apr 2030
Labor Day Wed 1 May 2030
Battle of Arica / Flag Day Fri 7 Jun 2030
Saints Peter and Paul Sat 29 Jun 2030
Air Force Day Tue 23 Jul 2030
Independence Day Sun 28 Jul 2030
Independence Day (2nd) Mon 29 Jul 2030
Battle of Junín Tue 6 Aug 2030
Saint Rose of Lima Fri 30 Aug 2030
Battle of Angamos Tue 8 Oct 2030
All Saints' Day Fri 1 Nov 2030
Immaculate Conception Sun 8 Dec 2030
Battle of Ayacucho Mon 9 Dec 2030
Christmas Wed 25 Dec 2030
New Year's Day Wed 1 Jan 2031
Maundy Thursday Thu 10 Apr 2031
Good Friday Fri 11 Apr 2031
Labor Day Thu 1 May 2031
Battle of Arica / Flag Day Sat 7 Jun 2031
Saints Peter and Paul Sun 29 Jun 2031
Air Force Day Wed 23 Jul 2031
Independence Day Mon 28 Jul 2031
Independence Day (2nd) Tue 29 Jul 2031
Battle of Junín Wed 6 Aug 2031
Saint Rose of Lima Sat 30 Aug 2031
Battle of Angamos Wed 8 Oct 2031
All Saints' Day Sat 1 Nov 2031
Immaculate Conception Mon 8 Dec 2031
Battle of Ayacucho Tue 9 Dec 2031
Christmas Thu 25 Dec 2031
New Year's Day Thu 1 Jan 2032
Maundy Thursday Thu 25 Mar 2032
Good Friday Fri 26 Mar 2032
Labor Day Sat 1 May 2032
Battle of Arica / Flag Day Mon 7 Jun 2032
Saints Peter and Paul Tue 29 Jun 2032
Air Force Day Fri 23 Jul 2032
Independence Day Wed 28 Jul 2032
Independence Day (2nd) Thu 29 Jul 2032
Battle of Junín Fri 6 Aug 2032
Saint Rose of Lima Mon 30 Aug 2032
Battle of Angamos Fri 8 Oct 2032
All Saints' Day Mon 1 Nov 2032
Immaculate Conception Wed 8 Dec 2032
Battle of Ayacucho Thu 9 Dec 2032
Christmas Sat 25 Dec 2032
New Year's Day Sat 1 Jan 2033
Maundy Thursday Thu 14 Apr 2033
Good Friday Fri 15 Apr 2033
Labor Day Sun 1 May 2033
Battle of Arica / Flag Day Tue 7 Jun 2033
Saints Peter and Paul Wed 29 Jun 2033
Air Force Day Sat 23 Jul 2033
Independence Day Thu 28 Jul 2033
Independence Day (2nd) Fri 29 Jul 2033
Battle of Junín Sat 6 Aug 2033
Saint Rose of Lima Tue 30 Aug 2033
Battle of Angamos Sat 8 Oct 2033
All Saints' Day Tue 1 Nov 2033
Immaculate Conception Thu 8 Dec 2033
Battle of Ayacucho Fri 9 Dec 2033
Christmas Sun 25 Dec 2033
New Year's Day Sun 1 Jan 2034
Maundy Thursday Thu 6 Apr 2034
Good Friday Fri 7 Apr 2034
Labor Day Mon 1 May 2034
Battle of Arica / Flag Day Wed 7 Jun 2034
Saints Peter and Paul Thu 29 Jun 2034
Air Force Day Sun 23 Jul 2034
Independence Day Fri 28 Jul 2034
Independence Day (2nd) Sat 29 Jul 2034
Battle of Junín Sun 6 Aug 2034
Saint Rose of Lima Wed 30 Aug 2034
Battle of Angamos Sun 8 Oct 2034
All Saints' Day Wed 1 Nov 2034
Immaculate Conception Fri 8 Dec 2034
Battle of Ayacucho Sat 9 Dec 2034
Christmas Mon 25 Dec 2034
New Year's Day Mon 1 Jan 2035
Maundy Thursday Thu 22 Mar 2035
Good Friday Fri 23 Mar 2035
Labor Day Tue 1 May 2035
Battle of Arica / Flag Day Thu 7 Jun 2035
Saints Peter and Paul Fri 29 Jun 2035
Air Force Day Mon 23 Jul 2035
Independence Day Sat 28 Jul 2035
Independence Day (2nd) Sun 29 Jul 2035
Battle of Junín Mon 6 Aug 2035
Saint Rose of Lima Thu 30 Aug 2035
Battle of Angamos Mon 8 Oct 2035
All Saints' Day Thu 1 Nov 2035
Immaculate Conception Sat 8 Dec 2035
Battle of Ayacucho Sun 9 Dec 2035
Christmas Tue 25 Dec 2035
New Year's Day Tue 1 Jan 2036
Maundy Thursday Thu 10 Apr 2036
Good Friday Fri 11 Apr 2036
Labor Day Thu 1 May 2036
Battle of Arica / Flag Day Sat 7 Jun 2036
Saints Peter and Paul Sun 29 Jun 2036
Air Force Day Wed 23 Jul 2036
Independence Day Mon 28 Jul 2036
Independence Day (2nd) Tue 29 Jul 2036
Battle of Junín Wed 6 Aug 2036
Saint Rose of Lima Sat 30 Aug 2036
Battle of Angamos Wed 8 Oct 2036
All Saints' Day Sat 1 Nov 2036
Immaculate Conception Mon 8 Dec 2036
Battle of Ayacucho Tue 9 Dec 2036
Christmas Thu 25 Dec 2036
New Year's Day Thu 1 Jan 2037
Maundy Thursday Thu 2 Apr 2037
Good Friday Fri 3 Apr 2037
Labor Day Fri 1 May 2037
Battle of Arica / Flag Day Sun 7 Jun 2037
Saints Peter and Paul Mon 29 Jun 2037
Air Force Day Thu 23 Jul 2037
Independence Day Tue 28 Jul 2037
Independence Day (2nd) Wed 29 Jul 2037
Battle of Junín Thu 6 Aug 2037
Saint Rose of Lima Sun 30 Aug 2037
Battle of Angamos Thu 8 Oct 2037
All Saints' Day Sun 1 Nov 2037
Immaculate Conception Tue 8 Dec 2037
Battle of Ayacucho Wed 9 Dec 2037
Christmas Fri 25 Dec 2037
New Year's Day Fri 1 Jan 2038
Maundy Thursday Thu 22 Apr 2038
Good Friday Fri 23 Apr 2038
Labor Day Sat 1 May 2038
Battle of Arica / Flag Day Mon 7 Jun 2038
Saints Peter and Paul Tue 29 Jun 2038
Air Force Day Fri 23 Jul 2038
Independence Day Wed 28 Jul 2038
Independence Day (2nd) Thu 29 Jul 2038
Battle of Junín Fri 6 Aug 2038
Saint Rose of Lima Mon 30 Aug 2038
Battle of Angamos Fri 8 Oct 2038
All Saints' Day Mon 1 Nov 2038
Immaculate Conception Wed 8 Dec 2038
Battle of Ayacucho Thu 9 Dec 2038
Christmas Sat 25 Dec 2038
New Year's Day Sat 1 Jan 2039
Maundy Thursday Thu 7 Apr 2039
Good Friday Fri 8 Apr 2039
Labor Day Sun 1 May 2039
Battle of Arica / Flag Day Tue 7 Jun 2039
Saints Peter and Paul Wed 29 Jun 2039
Air Force Day Sat 23 Jul 2039
Independence Day Thu 28 Jul 2039
Independence Day (2nd) Fri 29 Jul 2039
Battle of Junín Sat 6 Aug 2039
Saint Rose of Lima Tue 30 Aug 2039
Battle of Angamos Sat 8 Oct 2039
All Saints' Day Tue 1 Nov 2039
Immaculate Conception Thu 8 Dec 2039
Battle of Ayacucho Fri 9 Dec 2039
Christmas Sun 25 Dec 2039
New Year's Day Sun 1 Jan 2040
Maundy Thursday Thu 29 Mar 2040
Good Friday Fri 30 Mar 2040
Labor Day Tue 1 May 2040
Battle of Arica / Flag Day Thu 7 Jun 2040
Saints Peter and Paul Fri 29 Jun 2040
Air Force Day Mon 23 Jul 2040
Independence Day Sat 28 Jul 2040
Independence Day (2nd) Sun 29 Jul 2040
Battle of Junín Mon 6 Aug 2040
Saint Rose of Lima Thu 30 Aug 2040
Battle of Angamos Mon 8 Oct 2040
All Saints' Day Thu 1 Nov 2040
Immaculate Conception Sat 8 Dec 2040
Battle of Ayacucho Sun 9 Dec 2040
Christmas Tue 25 Dec 2040
New Year's Day Tue 1 Jan 2041
Maundy Thursday Thu 18 Apr 2041
Good Friday Fri 19 Apr 2041
Labor Day Wed 1 May 2041
Battle of Arica / Flag Day Fri 7 Jun 2041
Saints Peter and Paul Sat 29 Jun 2041
Air Force Day Tue 23 Jul 2041
Independence Day Sun 28 Jul 2041
Independence Day (2nd) Mon 29 Jul 2041
Battle of Junín Tue 6 Aug 2041
Saint Rose of Lima Fri 30 Aug 2041
Battle of Angamos Tue 8 Oct 2041
All Saints' Day Fri 1 Nov 2041
Immaculate Conception Sun 8 Dec 2041
Battle of Ayacucho Mon 9 Dec 2041
Christmas Wed 25 Dec 2041
New Year's Day Wed 1 Jan 2042
Maundy Thursday Thu 3 Apr 2042
Good Friday Fri 4 Apr 2042
Labor Day Thu 1 May 2042
Battle of Arica / Flag Day Sat 7 Jun 2042
Saints Peter and Paul Sun 29 Jun 2042
Air Force Day Wed 23 Jul 2042
Independence Day Mon 28 Jul 2042
Independence Day (2nd) Tue 29 Jul 2042
Battle of Junín Wed 6 Aug 2042
Saint Rose of Lima Sat 30 Aug 2042
Battle of Angamos Wed 8 Oct 2042
All Saints' Day Sat 1 Nov 2042
Immaculate Conception Mon 8 Dec 2042
Battle of Ayacucho Tue 9 Dec 2042
Christmas Thu 25 Dec 2042
New Year's Day Thu 1 Jan 2043
Maundy Thursday Thu 26 Mar 2043
Good Friday Fri 27 Mar 2043
Labor Day Fri 1 May 2043
Battle of Arica / Flag Day Sun 7 Jun 2043
Saints Peter and Paul Mon 29 Jun 2043
Air Force Day Thu 23 Jul 2043
Independence Day Tue 28 Jul 2043
Independence Day (2nd) Wed 29 Jul 2043
Battle of Junín Thu 6 Aug 2043
Saint Rose of Lima Sun 30 Aug 2043
Battle of Angamos Thu 8 Oct 2043
All Saints' Day Sun 1 Nov 2043
Immaculate Conception Tue 8 Dec 2043
Battle of Ayacucho Wed 9 Dec 2043
Christmas Fri 25 Dec 2043
New Year's Day Fri 1 Jan 2044
Maundy Thursday Thu 14 Apr 2044
Good Friday Fri 15 Apr 2044
Labor Day Sun 1 May 2044
Battle of Arica / Flag Day Tue 7 Jun 2044
Saints Peter and Paul Wed 29 Jun 2044
Air Force Day Sat 23 Jul 2044
Independence Day Thu 28 Jul 2044
Independence Day (2nd) Fri 29 Jul 2044
Battle of Junín Sat 6 Aug 2044
Saint Rose of Lima Tue 30 Aug 2044
Battle of Angamos Sat 8 Oct 2044
All Saints' Day Tue 1 Nov 2044
Immaculate Conception Thu 8 Dec 2044
Battle of Ayacucho Fri 9 Dec 2044
Christmas Sun 25 Dec 2044
New Year's Day Sun 1 Jan 2045
Maundy Thursday Thu 6 Apr 2045
Good Friday Fri 7 Apr 2045
Labor Day Mon 1 May 2045
Battle of Arica / Flag Day Wed 7 Jun 2045
Saints Peter and Paul Thu 29 Jun 2045
Air Force Day Sun 23 Jul 2045
Independence Day Fri 28 Jul 2045
Independence Day (2nd) Sat 29 Jul 2045
Battle of Junín Sun 6 Aug 2045
Saint Rose of Lima Wed 30 Aug 2045
Battle of Angamos Sun 8 Oct 2045
All Saints' Day Wed 1 Nov 2045
Immaculate Conception Fri 8 Dec 2045
Battle of Ayacucho Sat 9 Dec 2045
Christmas Mon 25 Dec 2045
New Year's Day Mon 1 Jan 2046
Maundy Thursday Thu 22 Mar 2046
Good Friday Fri 23 Mar 2046
Labor Day Tue 1 May 2046
Battle of Arica / Flag Day Thu 7 Jun 2046
Saints Peter and Paul Fri 29 Jun 2046
Air Force Day Mon 23 Jul 2046
Independence Day Sat 28 Jul 2046
Independence Day (2nd) Sun 29 Jul 2046
Battle of Junín Mon 6 Aug 2046
Saint Rose of Lima Thu 30 Aug 2046
Battle of Angamos Mon 8 Oct 2046
All Saints' Day Thu 1 Nov 2046
Immaculate Conception Sat 8 Dec 2046
Battle of Ayacucho Sun 9 Dec 2046
Christmas Tue 25 Dec 2046
New Year's Day Tue 1 Jan 2047
Maundy Thursday Thu 11 Apr 2047
Good Friday Fri 12 Apr 2047
Labor Day Wed 1 May 2047
Battle of Arica / Flag Day Fri 7 Jun 2047
Saints Peter and Paul Sat 29 Jun 2047
Air Force Day Tue 23 Jul 2047
Independence Day Sun 28 Jul 2047
Independence Day (2nd) Mon 29 Jul 2047
Battle of Junín Tue 6 Aug 2047
Saint Rose of Lima Fri 30 Aug 2047
Battle of Angamos Tue 8 Oct 2047
All Saints' Day Fri 1 Nov 2047
Immaculate Conception Sun 8 Dec 2047
Battle of Ayacucho Mon 9 Dec 2047
Christmas Wed 25 Dec 2047
New Year's Day Wed 1 Jan 2048
Maundy Thursday Thu 2 Apr 2048
Good Friday Fri 3 Apr 2048
Labor Day Fri 1 May 2048
Battle of Arica / Flag Day Sun 7 Jun 2048
Saints Peter and Paul Mon 29 Jun 2048
Air Force Day Thu 23 Jul 2048
Independence Day Tue 28 Jul 2048
Independence Day (2nd) Wed 29 Jul 2048
Battle of Junín Thu 6 Aug 2048
Saint Rose of Lima Sun 30 Aug 2048
Battle of Angamos Thu 8 Oct 2048
All Saints' Day Sun 1 Nov 2048
Immaculate Conception Tue 8 Dec 2048
Battle of Ayacucho Wed 9 Dec 2048
Christmas Fri 25 Dec 2048
New Year's Day Fri 1 Jan 2049
Maundy Thursday Thu 15 Apr 2049
Good Friday Fri 16 Apr 2049
Labor Day Sat 1 May 2049
Battle of Arica / Flag Day Mon 7 Jun 2049
Saints Peter and Paul Tue 29 Jun 2049
Air Force Day Fri 23 Jul 2049
Independence Day Wed 28 Jul 2049
Independence Day (2nd) Thu 29 Jul 2049
Battle of Junín Fri 6 Aug 2049
Saint Rose of Lima Mon 30 Aug 2049
Battle of Angamos Fri 8 Oct 2049
All Saints' Day Mon 1 Nov 2049
Immaculate Conception Wed 8 Dec 2049
Battle of Ayacucho Thu 9 Dec 2049
Christmas Sat 25 Dec 2049
New Year's Day Sat 1 Jan 2050
Maundy Thursday Thu 7 Apr 2050
Good Friday Fri 8 Apr 2050
Labor Day Sun 1 May 2050
Battle of Arica / Flag Day Tue 7 Jun 2050
Saints Peter and Paul Wed 29 Jun 2050
Air Force Day Sat 23 Jul 2050
Independence Day Thu 28 Jul 2050
Independence Day (2nd) Fri 29 Jul 2050
Battle of Junín Sat 6 Aug 2050
Saint Rose of Lima Tue 30 Aug 2050
Battle of Angamos Sat 8 Oct 2050
All Saints' Day Tue 1 Nov 2050
Immaculate Conception Thu 8 Dec 2050
Battle of Ayacucho Fri 9 Dec 2050
Christmas Sun 25 Dec 2050
New Year's Day Sun 1 Jan 2051
Maundy Thursday Thu 30 Mar 2051
Good Friday Fri 31 Mar 2051
Labor Day Mon 1 May 2051
Battle of Arica / Flag Day Wed 7 Jun 2051
Saints Peter and Paul Thu 29 Jun 2051
Air Force Day Sun 23 Jul 2051
Independence Day Fri 28 Jul 2051
Independence Day (2nd) Sat 29 Jul 2051
Battle of Junín Sun 6 Aug 2051
Saint Rose of Lima Wed 30 Aug 2051
Battle of Angamos Sun 8 Oct 2051
All Saints' Day Wed 1 Nov 2051
Immaculate Conception Fri 8 Dec 2051
Battle of Ayacucho Sat 9 Dec 2051
Christmas Mon 25 Dec 2051
New Year's Day Mon 1 Jan 2052
Maundy Thursday Thu 18 Apr 2052
Good Friday Fri 19 Apr 2052
Labor Day Wed 1 May 2052
Battle of Arica / Flag Day Fri 7 Jun 2052
Saints Peter and Paul Sat 29 Jun 2052
Air Force Day Tue 23 Jul 2052
Independence Day Sun 28 Jul 2052
Independence Day (2nd) Mon 29 Jul 2052
Battle of Junín Tue 6 Aug 2052
Saint Rose of Lima Fri 30 Aug 2052
Battle of Angamos Tue 8 Oct 2052
All Saints' Day Fri 1 Nov 2052
Immaculate Conception Sun 8 Dec 2052
Battle of Ayacucho Mon 9 Dec 2052
Christmas Wed 25 Dec 2052
New Year's Day Wed 1 Jan 2053
Maundy Thursday Thu 3 Apr 2053
Good Friday Fri 4 Apr 2053
Labor Day Thu 1 May 2053
Battle of Arica / Flag Day Sat 7 Jun 2053
Saints Peter and Paul Sun 29 Jun 2053
Air Force Day Wed 23 Jul 2053
Independence Day Mon 28 Jul 2053
Independence Day (2nd) Tue 29 Jul 2053
Battle of Junín Wed 6 Aug 2053
Saint Rose of Lima Sat 30 Aug 2053
Battle of Angamos Wed 8 Oct 2053
All Saints' Day Sat 1 Nov 2053
Immaculate Conception Mon 8 Dec 2053
Battle of Ayacucho Tue 9 Dec 2053
Christmas Thu 25 Dec 2053
New Year's Day Thu 1 Jan 2054
Maundy Thursday Thu 26 Mar 2054
Good Friday Fri 27 Mar 2054
Labor Day Fri 1 May 2054
Battle of Arica / Flag Day Sun 7 Jun 2054
Saints Peter and Paul Mon 29 Jun 2054
Air Force Day Thu 23 Jul 2054
Independence Day Tue 28 Jul 2054
Independence Day (2nd) Wed 29 Jul 2054
Battle of Junín Thu 6 Aug 2054
Saint Rose of Lima Sun 30 Aug 2054
Battle of Angamos Thu 8 Oct 2054
All Saints' Day Sun 1 Nov 2054
Immaculate Conception Tue 8 Dec 2054
Battle of Ayacucho Wed 9 Dec 2054
Christmas Fri 25 Dec 2054
New Year's Day Fri 1 Jan 2055
Maundy Thursday Thu 15 Apr 2055
Good Friday Fri 16 Apr 2055
Labor Day Sat 1 May 2055
Battle of Arica / Flag Day Mon 7 Jun 2055
Saints Peter and Paul Tue 29 Jun 2055
Air Force Day Fri 23 Jul 2055
Independence Day Wed 28 Jul 2055
Independence Day (2nd) Thu 29 Jul 2055
Battle of Junín Fri 6 Aug 2055
Saint Rose of Lima Mon 30 Aug 2055
Battle of Angamos Fri 8 Oct 2055
All Saints' Day Mon 1 Nov 2055
Immaculate Conception Wed 8 Dec 2055
Battle of Ayacucho Thu 9 Dec 2055
Christmas Sat 25 Dec 2055
New Year's Day Sat 1 Jan 2056
Maundy Thursday Thu 30 Mar 2056
Good Friday Fri 31 Mar 2056
Labor Day Mon 1 May 2056
Battle of Arica / Flag Day Wed 7 Jun 2056
Saints Peter and Paul Thu 29 Jun 2056
Air Force Day Sun 23 Jul 2056
Independence Day Fri 28 Jul 2056
Independence Day (2nd) Sat 29 Jul 2056
Battle of Junín Sun 6 Aug 2056
Saint Rose of Lima Wed 30 Aug 2056
Battle of Angamos Sun 8 Oct 2056
All Saints' Day Wed 1 Nov 2056

Preguntas frecuentes

What counts as a business day?

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