Day in, day out

We use this expression to talk about something that is repetitive and probably negative or boring.

You can use this phrase in ………… language.

 Spoken
 Written
 Informal

Example 1
A: How are you getting on with your job?
B: Not so great. The same routine day in, day out. It’s really dull.
Example 2
A: I could never work in a factory.   
B: Me neither. I couldn’t do a job where everything’s the same day in, day out.