4-On-4-Off Work Schedule Calculator
Enter your shift length, a date range, and where the start date falls in your rotation to count work days, days off, and hours — and see which dates you work.
4-On-4-Off Work Schedule Calculator calculates in your browser.
Count your work days and hours on a 4 on, 4 off rotation
A 4-on-4-off schedule — four days of work followed by four days off, repeating every eight days — is common in policing, manufacturing, oil and gas, and healthcare. Because eight days don’t divide into a week, the days you work drift across the calendar, and totals for a month or a year are awkward to count by hand. Enter your shift length, a start and end date, and where the start date falls in your rotation, and the calculator counts the work days, days off, and hours in that range, gives the average week, and lists your next stretches of work and time off with their dates.
How to use the 4-On-4-Off Work Schedule Calculator
- Type your shift length in hours, such as 12.
- Choose a start date (today by default) and an end date. Both dates are counted.
- Choose where the start date falls in your rotation: work day 1 to 4, or off day 1 to 4.
- Read the total hours, work days, days off, and weekly averages, and check the table of upcoming work and off days.
The formula
Days = end date − start date + 1
Work days = full 8-day cycles × 4 + work days in the leftover days
Hours = work days × shift length · Long-run week = shift length × 3.5
Dates are counted as calendar days on your own calendar, never as clock times, so a daylight-saving change or a leap day can’t add or lose a day. A year of 365 days is 45 full cycles plus 5 days, which is why the work days in a year come to 181, 182, 183, or 184 depending on where the year starts in the rotation.
| Shift length and dates | Work days | Total hours |
|---|---|---|
| 12-hour shifts, October 1, 2026 – December 31, 2026, starting on work day 1 | 48 days | 576 hours |
| 12-hour shifts, January 1, 2027 – December 31, 2027, starting on work day 1 | 184 days | 2,208 hours |
| 10-hour shifts, January 1, 2027 – December 31, 2027, starting on off day 1 | 181 days | 1,810 hours |
| 12-hour shifts, February 1, 2028 – February 29, 2028, starting on work day 3 | 14 days | 168 hours |
| 8-hour shifts, October 5, 2026 – November 1, 2026, starting on off day 2 | 13 days | 104 hours |
Calculated on your device
- The calculation runs in your browser as you type; nothing is sent to a server.
- Your dates, hours, and results are not sent to Looty Tools or stored.
- The calculator area is masked from session-recording analytics, so what you enter isn’t captured in recordings.
Limitations
- One shift per work day, all the same length. Swaps, overtime shifts, holidays, and leave are not included.
- It follows a strict 4 on, 4 off repeat. For other rotations, such as 2-2-3 or DuPont, use the Rotating Shift Hours Calculator.
- The table lists up to eight stretches of work and time off from the start date; the totals always cover the whole range.
- Ranges of up to 20 years and shifts of up to 24 hours.
Related calculators
- Night Shift Premium CalculatorEstimate extra pay for overnight hours, using the premium you enter.
- Rotating Shift Hours CalculatorAdd up hours across a rotating shift pattern.
- Days Between Dates CalculatorCount the days from one date to another.
Guides
- 4-On-4-Off ExplainedHow the 8-day 4-on-4-off cycle works, why your days off move one weekday each cycle, how often weekends fall off, and typical weekly hours.
- 4-On-4-Off Hours per YearThe average and exact work days and hours in a year on 4 on, 4 off, why the count is 181 to 184 days, leap years, and a comparison with 2,080 hours.
- Finding 4-On-4-Off Work DaysUse one known work day and the day count mod 8 to tell whether any future or past date is a work day or a day off, with a spreadsheet formula.
4-On-4-Off Work Schedule Calculator FAQ
- How many hours a week is a 4-on-4-off schedule?
- On average, 3.5 shifts a week — half of every 8 days. With 12-hour shifts that is 42 hours a week; with 10-hour shifts, 35. Individual weeks vary between 3 and 4 shifts because the 8-day cycle doesn’t line up with a 7-day week.
- How many days a year do you work on 4 on, 4 off?
- Half the year on average: 182.5 days. A 365-day year is 45 full cycles plus 5 days, so the actual count is between 181 and 184 depending on where the year starts in your rotation — 184 if January 1 is your first work day.
- What does "On the start date, you are on" mean?
- Where the start date falls in your 8-day rotation: work day 1 to 4, or off day 1 to 4. If your start date is the second day of a stretch of work, choose Work day 2, and the calculator lines up every date after it.
- Is the end date counted?
- Yes. The range includes both dates, so October 1 to December 31, 2026 is 92 days. Starting on work day 1 with 12-hour shifts, that is 48 work days and 576 hours.
- Can it show which dates I work?
- Yes. Below the totals, a table lists your work and off stretches with their dates — up to eight of them. For a single date further ahead, set the end date to that day and look at the last row.
- Are the hours and dates I enter sent anywhere?
- No. The calculation runs in your browser as you type. Your hours, dates, and results are not sent to Looty Tools or stored, and the calculator area is masked from session-recording analytics. Refreshing the page clears it.
