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3 weeks on 3 weeks off schedule calendar (21/21)

Twenty-one days working, then twenty-one days off, repeated. Two crews alternate, so one is always on site. That is about 183 shifts and 2,192 hours a year at 12 hours a shift, an average of 42 hours a week. Put your start date in below for your own 2027 calendar.

  • Free, no sign-up
  • Runs in your browser
  • Nothing uploaded or kept

How to use it

  1. Set your start date

    Enter a date from your roster that is the first day of a block, and say which block it is.

  2. Check the year

    Every shift and day off is drawn, with the hours a year, the days off and the weekends you have free.

  3. Print it or add it to your phone

    Download the calendar file, print the year, or copy the link to share it.

Pick a date you know from your roster; the whole year lines up with it.

Shift times and hours

42-day cycle: 21W 21O

Next 14 days

Shifts in 2027

189

Days off

176

of 365

Hours in 2027

2,268

12 h a shift

Average a week

42 h

Weekends fully off

25 of 52

Longest run

21 on

21 off at most

January 2027
MoTuWeThFrSaSu
Friday 1 January: shiftSaturday 2 January: shiftSunday 3 January: shift
Monday 4 January: shiftTuesday 5 January: shiftWednesday 6 January: shiftThursday 7 January: shiftFriday 8 January: shiftSaturday 9 January: shiftSunday 10 January: shift
Monday 11 January: shiftTuesday 12 January: shiftWednesday 13 January: shiftThursday 14 January: shiftFriday 15 January: shiftSaturday 16 January: shiftSunday 17 January: shift
Monday 18 January: shiftTuesday 19 January: shiftWednesday 20 January: shiftThursday 21 January: shiftFriday 22 January: day offSaturday 23 January: day offSunday 24 January: day off
Monday 25 January: day offTuesday 26 January: day offWednesday 27 January: day offThursday 28 January: day offFriday 29 January: day offSaturday 30 January: day offSunday 31 January: day off
February 2027
MoTuWeThFrSaSu
Monday 1 February: day offTuesday 2 February: day offWednesday 3 February: day offThursday 4 February: day offFriday 5 February: day offSaturday 6 February: day offSunday 7 February: day off
Monday 8 February: day offTuesday 9 February: day offWednesday 10 February: day offThursday 11 February: day offFriday 12 February: shiftSaturday 13 February: shiftSunday 14 February: shift
Monday 15 February: shiftTuesday 16 February: shiftWednesday 17 February: shiftThursday 18 February: shiftFriday 19 February: shiftSaturday 20 February: shiftSunday 21 February: shift
Monday 22 February: shiftTuesday 23 February: shiftWednesday 24 February: shiftThursday 25 February: shiftFriday 26 February: shiftSaturday 27 February: shiftSunday 28 February: shift
March 2027
MoTuWeThFrSaSu
Monday 1 March: shiftTuesday 2 March: shiftWednesday 3 March: shiftThursday 4 March: shiftFriday 5 March: day offSaturday 6 March: day offSunday 7 March: day off
Monday 8 March: day offTuesday 9 March: day offWednesday 10 March: day offThursday 11 March: day offFriday 12 March: day offSaturday 13 March: day offSunday 14 March: day off
Monday 15 March: day offTuesday 16 March: day offWednesday 17 March: day offThursday 18 March: day offFriday 19 March: day offSaturday 20 March: day offSunday 21 March: day off
Monday 22 March: day offTuesday 23 March: day offWednesday 24 March: day offThursday 25 March: day offFriday 26 March: shiftSaturday 27 March: shiftSunday 28 March: shift
Monday 29 March: shiftTuesday 30 March: shiftWednesday 31 March: shift
April 2027
MoTuWeThFrSaSu
Thursday 1 April: shiftFriday 2 April: shiftSaturday 3 April: shiftSunday 4 April: shift
Monday 5 April: shiftTuesday 6 April: shiftWednesday 7 April: shiftThursday 8 April: shiftFriday 9 April: shiftSaturday 10 April: shiftSunday 11 April: shift
Monday 12 April: shiftTuesday 13 April: shiftWednesday 14 April: shiftThursday 15 April: shiftFriday 16 April: day offSaturday 17 April: day offSunday 18 April: day off
Monday 19 April: day offTuesday 20 April: day offWednesday 21 April: day offThursday 22 April: day offFriday 23 April: day offSaturday 24 April: day offSunday 25 April: day off
Monday 26 April: day offTuesday 27 April: day offWednesday 28 April: day offThursday 29 April: day offFriday 30 April: day off
May 2027
MoTuWeThFrSaSu
Saturday 1 May: day offSunday 2 May: day off
Monday 3 May: day offTuesday 4 May: day offWednesday 5 May: day offThursday 6 May: day offFriday 7 May: shiftSaturday 8 May: shiftSunday 9 May: shift
Monday 10 May: shiftTuesday 11 May: shiftWednesday 12 May: shiftThursday 13 May: shiftFriday 14 May: shiftSaturday 15 May: shiftSunday 16 May: shift
Monday 17 May: shiftTuesday 18 May: shiftWednesday 19 May: shiftThursday 20 May: shiftFriday 21 May: shiftSaturday 22 May: shiftSunday 23 May: shift
Monday 24 May: shiftTuesday 25 May: shiftWednesday 26 May: shiftThursday 27 May: shiftFriday 28 May: day offSaturday 29 May: day offSunday 30 May: day off
Monday 31 May: day off
June 2027
MoTuWeThFrSaSu
Tuesday 1 June: day offWednesday 2 June: day offThursday 3 June: day offFriday 4 June: day offSaturday 5 June: day offSunday 6 June: day off
Monday 7 June: day offTuesday 8 June: day offWednesday 9 June: day offThursday 10 June: day offFriday 11 June: day offSaturday 12 June: day offSunday 13 June: day off
Monday 14 June: day offTuesday 15 June: day offWednesday 16 June: day offThursday 17 June: day offFriday 18 June: shiftSaturday 19 June: shiftSunday 20 June: shift
Monday 21 June: shiftTuesday 22 June: shiftWednesday 23 June: shiftThursday 24 June: shiftFriday 25 June: shiftSaturday 26 June: shiftSunday 27 June: shift
Monday 28 June: shiftTuesday 29 June: shiftWednesday 30 June: shift
July 2027
MoTuWeThFrSaSu
Thursday 1 July: shiftFriday 2 July: shiftSaturday 3 July: shiftSunday 4 July: shift
Monday 5 July: shiftTuesday 6 July: shiftWednesday 7 July: shiftThursday 8 July: shiftFriday 9 July: day offSaturday 10 July: day offSunday 11 July: day off
Monday 12 July: day offTuesday 13 July: day offWednesday 14 July: day offThursday 15 July: day offFriday 16 July: day offSaturday 17 July: day offSunday 18 July: day off
Monday 19 July: day offTuesday 20 July: day offWednesday 21 July: day offThursday 22 July: day offFriday 23 July: day offSaturday 24 July: day offSunday 25 July: day off
Monday 26 July: day offTuesday 27 July: day offWednesday 28 July: day offThursday 29 July: day offFriday 30 July: shiftSaturday 31 July: shift
August 2027
MoTuWeThFrSaSu
Sunday 1 August: shift
Monday 2 August: shiftTuesday 3 August: shiftWednesday 4 August: shiftThursday 5 August: shiftFriday 6 August: shiftSaturday 7 August: shiftSunday 8 August: shift
Monday 9 August: shiftTuesday 10 August: shiftWednesday 11 August: shiftThursday 12 August: shiftFriday 13 August: shiftSaturday 14 August: shiftSunday 15 August: shift
Monday 16 August: shiftTuesday 17 August: shiftWednesday 18 August: shiftThursday 19 August: shiftFriday 20 August: day offSaturday 21 August: day offSunday 22 August: day off
Monday 23 August: day offTuesday 24 August: day offWednesday 25 August: day offThursday 26 August: day offFriday 27 August: day offSaturday 28 August: day offSunday 29 August: day off
Monday 30 August: day offTuesday 31 August: day off
September 2027
MoTuWeThFrSaSu
Wednesday 1 September: day offThursday 2 September: day offFriday 3 September: day offSaturday 4 September: day offSunday 5 September: day off
Monday 6 September: day offTuesday 7 September: day offWednesday 8 September: day offThursday 9 September: day offFriday 10 September: shiftSaturday 11 September: shiftSunday 12 September: shift
Monday 13 September: shiftTuesday 14 September: shiftWednesday 15 September: shiftThursday 16 September: shiftFriday 17 September: shiftSaturday 18 September: shiftSunday 19 September: shift
Monday 20 September: shiftTuesday 21 September: shiftWednesday 22 September: shiftThursday 23 September: shiftFriday 24 September: shiftSaturday 25 September: shiftSunday 26 September: shift
Monday 27 September: shiftTuesday 28 September: shiftWednesday 29 September: shiftThursday 30 September: shift
October 2027
MoTuWeThFrSaSu
Friday 1 October: day offSaturday 2 October: day offSunday 3 October: day off
Monday 4 October: day offTuesday 5 October: day offWednesday 6 October: day offThursday 7 October: day offFriday 8 October: day offSaturday 9 October: day offSunday 10 October: day off
Monday 11 October: day offTuesday 12 October: day offWednesday 13 October: day offThursday 14 October: day offFriday 15 October: day offSaturday 16 October: day offSunday 17 October: day off
Monday 18 October: day offTuesday 19 October: day offWednesday 20 October: day offThursday 21 October: day offFriday 22 October: shiftSaturday 23 October: shiftSunday 24 October: shift
Monday 25 October: shiftTuesday 26 October: shiftWednesday 27 October: shiftThursday 28 October: shiftFriday 29 October: shiftSaturday 30 October: shiftSunday 31 October: shift
November 2027
MoTuWeThFrSaSu
Monday 1 November: shiftTuesday 2 November: shiftWednesday 3 November: shiftThursday 4 November: shiftFriday 5 November: shiftSaturday 6 November: shiftSunday 7 November: shift
Monday 8 November: shiftTuesday 9 November: shiftWednesday 10 November: shiftThursday 11 November: shiftFriday 12 November: day offSaturday 13 November: day offSunday 14 November: day off
Monday 15 November: day offTuesday 16 November: day offWednesday 17 November: day offThursday 18 November: day offFriday 19 November: day offSaturday 20 November: day offSunday 21 November: day off
Monday 22 November: day offTuesday 23 November: day offWednesday 24 November: day offThursday 25 November: day offFriday 26 November: day offSaturday 27 November: day offSunday 28 November: day off
Monday 29 November: day offTuesday 30 November: day off
December 2027
MoTuWeThFrSaSu
Wednesday 1 December: day offThursday 2 December: day offFriday 3 December: shiftSaturday 4 December: shiftSunday 5 December: shift
Monday 6 December: shiftTuesday 7 December: shiftWednesday 8 December: shiftThursday 9 December: shiftFriday 10 December: shiftSaturday 11 December: shiftSunday 12 December: shift
Monday 13 December: shiftTuesday 14 December: shiftWednesday 15 December: shiftThursday 16 December: shiftFriday 17 December: shiftSaturday 18 December: shiftSunday 19 December: shift
Monday 20 December: shiftTuesday 21 December: shiftWednesday 22 December: shiftThursday 23 December: shiftFriday 24 December: day offSaturday 25 December: day offSunday 26 December: day off
Monday 27 December: day offTuesday 28 December: day offWednesday 29 December: day offThursday 30 December: day offFriday 31 December: day off
  • W shift
  • · day off
See every crew side by side

With all the crews working this pattern, exactly one crew is on every day. One cycle of 42 days, then it repeats.

Day123456789101112131415161718192021222324252627282930313233343536373839404142
Your crewWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshift·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off
Other crew·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day off·day offWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshiftWshift

Check the result against your roster: employers run these patterns in slightly different ways.

How the 3 weeks on 3 weeks off pattern works

The 42-day cycle means eight or nine trips to site a year, each three weeks long. Because 42 is a multiple of 7, your blocks keep the same days of the week, but only every sixth week lines up with the same date of the month.

Also searched for as: 21 on 21 off, 21/21 rotation, three weeks on three weeks off.

The cycle is 42 days long: 21 shifts, 21 days off, and then it starts again.

The blocks of the cycle

BlockWhatDays of the cycle
121 shiftsDays 1 to 21
221 days offDays 22 to 42

The numbers

Cycle length42 days
Shifts in a cycle21 of 42 days
Shifts a yearabout 183
Days off a yearabout 183
Hours a year (at 12 h a shift)about 2,192
Average hours a week42
Longest run of shifts21
Longest break21 days

A year is 365.25 days on average, so the yearly figures are averages; the calendar above counts the exact days of the year you pick.

Good and bad about 3 weeks on 3 weeks off

In its favour

  • Few trips to site
  • Three full weeks at home at a time
  • Half the year free

Against it

  • Three weeks away is a long time
  • A single missed event can fall inside a hitch
  • Fatigue builds over the hitch

Who uses 3 weeks on 3 weeks off

Used in remote and offshore work, expedition and camp-based roles, where fewer, longer trips cost less than many short ones.

Employers run these patterns in slightly different ways, and a union contract or roster can differ from the version here. The grid above is exact for the cycle shown: if your roster differs, choose “My own cycle” in the calendar and type it in.

Other shift patterns

All shift patterns and the cycle builder

Frequently asked questions

How many hours a week is 3 weeks on 3 weeks off?

On average 42 hours a week, at 12 hours a shift: 21 shifts in every 42-day cycle. The weeks are not all alike, so a single week can hold more or fewer hours than the average. Change the shift length in the calendar and every number follows.

How many days off a year do I get on 3 weeks on 3 weeks off?

About 183 days off in a 365-day year and about 183 shifts, with a longest run of 21 shifts and a longest break of 21 days. Put your real start date in the calendar for the exact count in your year, including how many weekends are fully off.

How many days off a year is 3 weeks on 3 weeks off?

Half the year: about 183 days. The calendar above gives the exact days for the year you pick.

Can I put the 3 weeks on 3 weeks off pattern in Google Calendar or on my phone?

Yes. Pick your start date, press Add to my calendar, and open the .ics file in Google Calendar, Apple Calendar or Outlook. Each shift has a fixed ID, so importing the file again later replaces your shifts instead of adding a second set.

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