How long can eggs stay out?

Your 12 hours will not be a problem. The eggs in the United States that you purchase in the grocery store have been washed and cleaned with bleach to get off any "poo" on there from the chicken so the protective coating on them is gone. With the coating gone, air and bacteria can get into the egg. They don't do that in Europe so the natural protective coating from the chicken is there to keep the egg sealed.

We used to raise chickens and as long as you turn the eggs every day or two, the eggs will last for quite some time. But if the eggs are fertile, then you need to keep the temperature below 70 degrees. Seventy degrees is the beginning temperature where the eggs will start to grow but not warm enough to fully incubate (that's 98 to 100 degrees). So if your temperature is above 70 and they start to grow, they will die and rot.

But for your 12 hours, again there is no worry. Feel free to use them.

Eggs really do not need to be refrigerated, so long as the temperature in the house is not above 85 degrees or so for a period of time.

For the sake of safety however, if you bought them from the grocery store fridge, keep them there. As to leaving them out? No more than room temperature for a few hours.

I keep a crate of eggs in the back bedroom! It is cool in there! I do not put the flat in the fridge when I bring it to the kitchen, instead putting the eggs into a basket! They are always ready to use for my baking! Baking recipes always say room temperature eggs! I can use the last flat from the crate before the end of the month! Europeans do not ever refrigerate their eggs! They do as I do and leave them at room temperature. Yes, even in the desert southwest in the summer they are fine!

Eggs can stay out for days as long as they are not in direct sunlight they will not spoil! They are still good to make that omelet!

Considering in many countries eggs are never refrigerated I think your good

Eggs do not need to be refrigerated. They can sit at room temperature- unless you cooked them or boiled them. Raw eggs, still in their uncracked shells, can be stored at room temperature or in the fridge. They won't go off unless they pass their expiry date.!

Eggs do not need to be kept in the fridge at all, and there is a lot to be said for keeping them at room temperature

3 or 4 weeks

Eggs don't need to be kept in the fridge. End of story.

2 weeks or so. Eggs do NOT need to be refeidgerated.