3-4-4-3
Three nights, four nights, four nights, three nights, across two weeks. An even split with the same weekdays every week.
Parent A: 7 nights · Parent B: 7 nights · repeats every 14 days.
What it is like
Similar to 2-2-5-5 in spirit, with the days arranged differently. Each parent holds a consistent stretch of the week rather than scattered days.
One thing to know before you pick it. In the common arrangement, one parent ends up with every weekend and the other with the weekdays. That is a deliberate choice for some families and a nasty surprise for others.
Suits
Families where one parent works weekends and the other does not, since the schedule matches real life rather than fighting it. Parents who want long, predictable blocks without a full week apart.
Harder if
You both want weekend time with the kids. If that is the case, look at 2-2-5-5 instead, where weekends alternate.
The mistake people make
Not noticing the weekend distribution until it has been running for a month. Look at a full fortnight on a calendar before agreeing to it.
Try it with your own dates
Runs entirely in your browser, generated from the same logic as the app. No account, no data sent anywhere.
Putting it on a calendar
Once you have picked something, the app will build it. Choose the pattern, set the start date, and it writes the whole schedule into a shared calendar both houses can see. Change it later and it rebuilds without you redoing the year by hand.
One calendar is free, which is all this needs.