The four-day week has trials, books, a global nonprofit, and a permanent slot in the discourse. We wanted the version that shows up in writing, so we searched all 110,681 postings in our corpus for any mention of a four-day, compressed, or reduced week. The count came back at 102 postings, or 0.09 percent.
One in eleven hundred. Whatever the four-day week is right now, it is not yet a thing employers commit to in the job ad.
The four species, because they are not one thing
| Format | Hours | Pay | Your hourly rate |
|---|---|---|---|
| 100-80-100 | ~32 in 4 days | Full | Rises ~25% |
| Compressed 4x10 | 40 in 4 days | Full | Unchanged, days longer |
| 9-day fortnight | ~72 in 9 days | Full | Rises ~11% |
| Reduced hours | 32 or 36 | Often prorated | Check the letter |
The distinction matters more than the branding. The celebrated UK pilot ran on 100-80-100: 61 companies, full pay for 80 percent of the hours, and afterward 56 kept going, with sick days down 65 percent and revenue roughly flat. A compressed 4x10 gives you the same Friday but none of the raise; it moves ten hours, it does not remove them. Two offers can both say four-day week and differ by a quarter of your effective wage.
Who actually offers it, in writing
Now our 102. By format: 57 say four-day week without specifying, 38 offer a 9-day fortnight, four name reduced hours, three name 4x10. And the occupations at the top of the list are not the ones the discourse predicts: civil engineers and electricians lead with six postings each, then financial analysts, welders, chefs, and compliance officers. Architects and architectural technologists appear too. Software roles barely register.
The fortnight number explains part of it. The 9-day fortnight is an established UK arrangement, common in engineering and public sector work, and our UK sources carry it into the corpus. It is the four-day week's older, quieter cousin: alternating five and four day weeks, every other Friday off, no manifesto attached. Firms that already run it just say so in the ad, which is exactly why it outnumbers the headline model in real postings.
Reading an offer without getting fooled
Three questions sort any four-day claim in under a minute. Are the hours reduced or rearranged, since 32 at full pay is a raise and 4x10 is a schedule. Is it in the contract or in the culture deck, because a trial can end and a term cannot. And does it survive seniority, as some firms quietly restore the fifth day above a certain level. The Tokyo government, which moved its workforce to a four-day option in April 2025, put it in policy. A startup putting it in a careers-page banner has made a softer promise.
Where this leaves you
If a four-day week matters to you, the data suggests looking in unexpected places: UK engineering and construction firms are writing it into ads while famous tech names are marching the other direction entirely. And when you find one, do the hourly math before celebrating. The difference between the species is the difference between a 25 percent raise and a longer Tuesday.
Corpus count: regex over description text of 110,681 raw postings, PivotHop July 2026 (patterns: four-day week, 4x10, 32/36-hour week, 9-day fortnight, 100-80-100). Counts are floors; ads can omit benefits. UK pilot figures: 4 Day Week Global and Autonomy Institute reporting, 2023, with follow-up trials through 2025. Tokyo: Tokyo Metropolitan Government announcements, effective April 2025. Formats and hourly math: our own arithmetic on stated terms.