Have you ever come back from a trip and noticed your digital clocks flashing the wrong time? That’s a sure sign the power went out — and it often raises the big question: Is the food in your freezer still safe to eat?

A woman named Sheila Pulanco Russell shared a smart little hack on Facebook that can help ease that worry.

All you need is a mug, some water, and a coin — things you likely already have at home. Just fill the mug with tap water, freeze it, and once it’s frozen solid, place a quarter on top. If you return and the quarter is at the bottom of the mug, it means the ice melted completely and refroze, which is a red flag — your food likely spoiled. But if the quarter is still at the top or somewhere in the middle, chances are your food stayed frozen and is still safe.

It’s a simple way to avoid tossing out perfectly good food — or worse, eating something that’s no longer safe.

This quick trick can help you save money, reduce waste, and give you peace of mind after a power outage. Share it with friends and family — it’s an easy step that can make a big difference in protecting your food.