It's not or it isn't

[timeserved]

As per title.
To say:

It is not lunch time yet
It is not urgent
etc
if you like "it's not" vote UABU, or it isn't UANBU

It's not a big deal, and it isn't something I'd get worked up about.

They both mean exactly the same. if you are being pedantic, you could use “it’s not” when speaking only and use “it is not” when writing it down, I suppose…

Nicely done 😆