Compressed Workweek Calculator
Updated August 2026 · Free · No sign-up
Plan a compressed workweek — 4/10s, 9/80s, or a 4-day week — and see exactly what your daily hours, days off per year, and overtime exposure look like under each schedule.
Quick answer: A 4/10 schedule = four 10-hour days for the same 40 hours and 52 extra days off per year. A 9/80 = eight 9-hour days + one 8-hour day over two weeks, yielding 26 three-day weekends annually. Total hours stay the same; the shape changes.
The Main Compressed Schedules
| Schedule | Pattern | Weekly hours | Extra days off/yr |
|---|---|---|---|
| 4/10 | 4 days × 10 hrs | 40 | 52 |
| 9/80 | 8×9 + 1×8 over 2 weeks, alt. Friday off | 40 avg | 26 |
| True 4-day week | 4 × 8 hrs, full pay (100-80-100 model) | 32 | 52 |
| 3/12 | 3 × 12 hrs (nursing/manufacturing) | 36 (often paid as 40) | 104 |
Worked Examples
Example 1 — 4/10 commute math. A 45-minute each-way commuter saves 52 round trips = 78 hours/year — two full working weeks recovered, before counting the childcare day or the errands that no longer eat Saturday.
Example 2 — 9/80 payroll mechanics. The week is redefined to start mid-Friday so each week contains exactly 40 hours — done right, no overtime triggers; done sloppily (week starting Monday), week one has 44 hours and legally owes OT.
Example 3 — daily-OT states. California pays OT beyond 8 hours/day — but a properly adopted alternative workweek schedule (two-thirds employee vote, filed with the state) permits 10-hour days without daily OT. A 4/10 in a daily-OT state without that process owes 2 OT hours every day: $25/hr × 2 × 1.5 = $75/day of accidental liability.
Overtime Traps by Schedule
- 4/10: fine under federal FLSA (weekly 40 trigger); daily-OT states (CA, AK, NV, CO variants) need the alternative-schedule process. Any 5th day worked is instant OT territory.
- 9/80: entirely dependent on the redefined workweek boundary splitting the 8-hour Friday — audit the payroll configuration, not the intention. Details on the OT math: overtime pay calculator.
- 3/12: 12-hour days in daily-OT states owe daily premiums unless exempted; healthcare has specific carve-outs. Watch meal/rest break multipliers on long shifts.
What the Evidence Says (4-Day Week Trials)
Large pilots (UK 2022, subsequent multi-country trials) consistently report maintained or improved output, sharply lower burnout, and single-digit-percent revenue effects — with the caveat that participating firms self-selected. The pattern that holds across studies: compressed hours force meeting discipline — the productivity gain is mostly recovered meeting time (price yours with the meeting cost calculator). Where it struggles: coverage-based roles (support, healthcare) where fewer days means hiring more heads, not just scheduling better.
Proposing It To Your Employer
- Pilot, not policy: propose 8-12 weeks with defined success metrics — output, availability windows, customer response times.
- Solve coverage first: pair with a teammate on opposite days off; present the coverage map, not just your preference.
- Anticipate the daily-OT question if you're hourly in a daily-OT state — bring the alternative-schedule answer.
- PTO accounting note: on a 4/10, one vacation day burns 10 PTO hours, not 8 — recheck balances with the PTO accrual calculator.
Frequently Asked Questions
What is a 4/10 compressed workweek?
Four 10-hour days totaling the same 40 hours — same pay, 52 extra days off per year, and no federal overtime since the weekly trigger stays at 40.
How does a 9/80 schedule work?
Over two weeks: eight 9-hour days plus one 8-hour day, with alternate Fridays off. Payroll must split the workweek mid-Friday so each week holds exactly 40 hours.
Does a compressed week trigger overtime?
Not federally (weekly 40 trigger). Daily-OT states like California require an alternative workweek schedule vote/filing to run 10-hour days without daily OT.
Is a 4-day week the same as a compressed week?
No — compressed schedules keep 40 hours in fewer days; the true 4-day week (100-80-100 model) cuts to ~32 hours at full pay for maintained output.
How does PTO work on a 4/10 schedule?
A day off costs 10 hours of PTO instead of 8 — the same annual PTO bank buys fewer compressed days.
Do 4-day week trials actually work?
Major pilots report maintained output and lower burnout, largely from recovered meeting time — with weaker results in coverage-based roles needing constant staffing.
✓ Formula verified • Last updated: August 20, 2026