Can You Microwave Metal? (Answered)

Can You Microwave Metal

Microwaves have become a staple appliance in many households, making meal prep and reheating leftovers quick and easy. However, there is a lot of conflicting information regarding the safety of microwaving metal. 

Some people believe that putting any metal in the microwave can cause a dangerous explosion or damage the appliance. In this article, we will explore the truth about microwaving metal and provide information on how to do it safely.

Key Takeaways:

  • Some metals can be safely used in the microwave.
  • Not all metals are safe to microwave, and it’s important to know which metals are microwave-safe. Smooth and thick metals are unlikely to arc, while metals with sharp edges or multiple pieces next to each other can create sparks and arcing.
  • Always check the owner’s manual for specific instructions on what can be microwaved, and use approved materials and containers.
  • Use small pieces of metal wisely to prevent overcooking, and always follow package instructions.
  • If unsure about microwaving a dish or material, opt for glass or other known safe materials.

What Happens When Metal is Microwaved?

To understand the safety of microwaving metal, it’s important to know what happens when metal is exposed to microwaves.

Microwaves are electromagnetic waves that cause the molecules in food to vibrate rapidly, producing heat. While metal doesn’t contain water molecules like food does, it can still interact with microwaves.

Metals are made up of a network of atoms with loose electrons floating around them. When microwaves come into contact with metal, the waves attract these loose electrons, causing them to bounce around.

When metal with sharp edges or pointy angles that are right next to each other comes into contact with microwaves, the electrons are ping-ponged back and forth, creating a concentration of negative charge.

This creates sparks and can result in a phenomenon known as arcing, which is when an electric current jumps from one piece of metal to another.

When Is Metal Safe in the Microwave?

Not all metal is safe to microwave, and it’s essential to know which metals are microwave-safe. Metal is generally reflective of microwaves, which is why the walls of microwaves are metal to allow the waves to bounce around inside and cook food. 

Smooth and thick metals, such as a spoon or a microwave-safe lid with a rounded rim, are unlikely to arc. Additionally, microwaves do not penetrate metal deeply, so thick metal will heat up slowly and not burn or spark.

However, there are some types of metal that should never be microwaved. For instance, if there are multiple pieces of metal next to each other, like the tines of a fork, this can create sparks and arcing. 

The same is true for metal with extremely thin or sharp edges, like aluminum foil or the gold trim on tea cups or plates. When in doubt, check the owner’s manual for specific instructions regarding what can be microwaved in the appliance.

Tips For Microwaving With Metal

When microwaving with metal, it is important to follow some basic tips to avoid any potential danger.

Firstly, always check the owner’s manual of your microwave to see if it is safe to use materials like aluminum foil, metal trays, and food packaging like popcorn bags. It is essential to follow the guidelines specific to your oven to ensure safety.

Secondly, always use approved materials and containers. The USDA has a list of safe and unsafe containers for microwaving, as well as guidelines for cooking safely. 

You can use materials like aluminum foil safely in small quantities as long as your owner’s manual gives the blessing. Make sure the foil is new and smooth, not crumpled. Do not heat any dinnerware with metal trim unless it is specifically designed for microwave use.

Also, avoid zapping takeout food containers with metal handles or twist ties. One big thing to avoid is arcing, which is when an electric current jumps from one piece of metal to another, such as from spot to spot on the gold rim of a dish or from peak to peak on crumpled foil. In addition to ruining your plate, arcing can potentially damage your oven or start a fire.

Thirdly, use metal wisely. It’s important to understand the role of metal in the microwave. It functions as a shield, blocking the waves emitted by the oven. For that reason, food manufacturers often use metal in packaging to help foods cook more evenly by shielding one part of a dish. You can use small pieces of metal to prevent the corners of brownies or the ends of lasagna from overcooking.

Fourthly, always follow your package ‘s instructions. Many packaged, microwavable foods rely on metal for a variety of functions. In popcorn bags, metal susceptors help promote even and thorough popping. 

Susceptors are also used in microwavable pizza packaging to help create a crispy crust. These metals are perfectly safe in the microwave, just make sure to cook according to the directions.

Lastly, if you’re ever unsure about heating a dish in the microwave or don’t feel safe, don’t do it. Opt for glass or other materials you know can be safely microwaved.


1. Can you microwave a metal bowl?

You can’t microwave metal bowls. Metal reflects microwaves, preventing food from heating properly. Sharp edges also risk dangerous arcing/sparks inside the microwave which can lead to fire. Use only microwave-safe containers.


In conclusion, microwaving with metal can be safe if you follow the proper precautions. While there is some truth to the popular belief that metal cannot be microwaved, some metals can be safely used in the microwave. 

It is essential to understand the science behind microwaving metal, avoid arcing, and use approved materials and containers. When microwaving with metal, always follow the guidelines provided by your microwave’s owner’s manual and the instructions on the food packaging. 

By doing so, you can ensure a safe and efficient cooking experience while using your microwave.

By Rosie Elliott

I’m Rosie. I’m a professional chef with experience in Western, Mediterranean, and Italian cuisine. I’ve been cooking for over 15 years, and I have two daughters that keep me busy!