I made a batch of royal icing ,and had left it out overnight. Can anyone please tell me what the shelf life for Royal icing is both refridgerated and not? Thank you for your help

I left some out (covered in saran and foil) for a few days. Gave it a big stir to re-blend and it worked out fine.

It last awhile outside, but the consistency changes a bit. So usually the leftovers I use more for piping, since for flowers I prefer much a perfect consistency.
Edna

Depends on what you made it with....fresh egg whites, or meringue powder?