Weeks! You don't even want to know how old store bought eggs are, and they are often left in the back without refrigeration. you can give them the float test before you boil them.
If they sink right down, they're safe for human consumption.
If they lift up on one end but still rest on the bottom of the bowl/pitcher/whatever, they're still good but use them first, there's more air in them.
If they rise off the bottom but not too high, (say an inch or so) I feed them back to hens or dogs since I have a surplus, if I was 'hurting' for food or supplies, I'd still use them, maybe for baking etc.
If they rise say more than an inch or two, I wouldn't eat them but definitely still safe for chickens.
If they come to the top, I wouldn't eat them or feed them.