I have a set of eggs that expired last week, would they still be okay to cook with? Generally in the USA, can refrigerated eggs be used past their expiration date?
Yes, you can use eggs well past their "sell by" date. A week past shouldn't have a noticeable difference.
The older the eggs get, the more evaporation that will take place (because the eggs are washed, so they don't have a protective layer).
You will notice in older eggs that there's a growing pocket of air inside the egg when you break them. (for me it tends to be on the more rounded end, but I don't know if it has to do with how you orient the eggs in storage).
I know that I've used eggs more than a month past the "sell by" date, and I wouldn't be surprised if I've gone two months. It's only really a problem in baking, as the egg whites won't contribute the same amount of moisture as if they were fresh. And maybe for hard boiled eggs if you want them pretty, as you'll end up with a void where the air pocket is.