Founder here :) Thanks for the submission!

There are now 50 companies with a 4 day work week in the database but I'm finding more and more each day so check back soon, I have more to add

Are these jobs offering the same salary or 80% of the market rate?

Usually there is no drop in salary

i.e. most of these companies previously worked 5 days per week and then switched to a 4 day week without loss in salary