Does Ryanair measure / check the size of hand & cabin baggage ?

Should I expect, that Ryanair will check the size dimensions of my hand baggage and cabin baggage on the airport ?

I don't think they are checking the size of every hand luggage or cabin luggage. I would say, when the lugagge looks like it is exceeding the maximum allowed dimensions, they will probably measure it.

There are baggage size checking stands often placed on airports. You may be asked to fit the baggage into the measuring stand.

Ryanair has also introduced the mobile application, which scans baggage to check whether it fits within its measurements.