Will Running A Microwave With Nothing In It Ruin It

Running a microwave with nothing in it can be a common occurrence in many households. I’ve definitely been guilty of quickly hitting the start button without putting anything inside. But what are the consequences of doing this? Will it actually ruin the microwave?

What Happens When You Run an Empty Microwave?

When you run an empty microwave, the electromagnetic waves produced by the magnetron can’t be absorbed by food, so they end up being reflected around the inside of the microwave. This can lead to a buildup of energy, which can potentially damage the microwave or the magnetron itself.

The microwave is designed to heat food, not the air or the empty space inside it. Running it empty means the energy has nowhere to go, which can cause damage to the microwave’s internal components over time. It’s similar to running a car engine without any oil or a fan without any blades – it’s just not meant to operate that way.

Can It Cause Harm?

While running an empty microwave once or twice might not immediately ruin it, repetitive use in this manner could ultimately lead to damage. The excess energy bouncing around the microwave can potentially cause the magnetron to burn out, which is a crucial and expensive part to replace.

Safety Concerns

Besides the potential damage to the microwave, there are also safety concerns to consider. The buildup of energy can create excessive heat, which might pose a fire hazard. Additionally, if the microwave is run without anything to absorb the energy, the waves can be reflected back to the magnetron, which may cause electrical arcing and damage the microwave further.


Although it might be tempting to quickly heat up an empty mug or a plate, it’s best to avoid running a microwave without anything in it. Over time, it could lead to costly repairs or even become a safety hazard. Remember to always place a microwave-safe item inside before you hit that start button!