Can You Put Aluminium Foil in a Microwave?

Most of us, I included, use aluminum foil for baking and packaging food to prevent it from losing moisture. It can also wrap delicate food like veggies when grilling. 

Aluminum foil is typically a thin sheet of silvery metal that serves different purposes. Can you put aluminum foil in a microwave? 

Can You Put Aluminium Foil in a Microwave?

The simple answer is yes! You can put it in a microwave. However, it’s risky at times as it can easily start a fire if there is any sparks build up inside the microwave or smoke.

However, certain precautions should be considered when putting it in your microwave.

Let’s take a look!

Tips To Take Into Consideration When Using Aluminum Foil

  • You should never cover the food entirely with Aluminum foil when microwaving. The electric currents overwhelm it, causing it to heat pretty fast, leading to sparking. 
  • Since Aluminum Foils obstruct microwaves, you can cover the sections of food you want to safeguard from burning. The open surface area of the food should always be bigger than the foil- you should only cover a quarter of the food with foil.
  • The Aluminum Foil features two sides, the dull one and the shiny one, but it doesn’t matter which side you cover the food with; they are both fine.
  • The Foil strips shouldn’t be too thin; they should be a bit bigger than a square inch as they can turn into antennas that centralize microwaves.
  • You should mold the foil smoothly with just a few wrinkles. Wrinkles can easily cause sparks which can then cause a fire.
  • Foods that come in foil containers are microwaved directly, but always ensure you follow instructions written on the pack by the manufacturer.
  • Before placing a Foil container inside the microwave, you should remove the lid as the waves can’t penetrate the container when it’s closed unless stated otherwise.
  • Aluminum cookware or food wrapped in foil should be set in the middle of the microwave to ensure they don’t come into contact with the metallic walls of the microwave. If the turntable is metallic, you should place a non-metal platter beneath the aluminum cookware or foil wrap. 
  • If you notice the sparks, turn off the microwave immediately, remove it and get an alternative, like a microwave-safe dish.

What Happens When Aluminum Foil Is Placed In A Microwave?

Having metallic walls inside the microwave doesn’t necessarily mean they’ll cause any danger. Aluminum foil is usually thin, so once food begins to heat up, the water turns into moisture, producing energy. 

Since food is covered in foil, there’s no way for the energy to get out, making it heat up fast.

Why Is It Not Safe To Use Aluminum Foil In A Microwave?

  1. Using aluminum foil in microwaves can sometimes lead to sparking because it’s metal. Sparking can permanently damage the microwave’s interior, meaning you will have to spend a large sum of money to get a new one or repair it. 
  2. Reheating or cooking food wrapped with foil in a microwave can be difficult. Microwaves work by producing energy that targets water molecules in food, causing them to vibrate. The vibration leads to friction, producing heat that cooks the food. Since foil is a metal, wrapping up food with it obstructs the radiation from reaching the food, so you might end up having uncooked food because it has a poor heating effect.
  3. Allowing the magnetron to keep generating microwaves, yet no food molecules are being targeted, is one of the easiest ways to damage the interior parts of the microwave. In other words, wrapping up food using foil completely and putting it in a microwave is just like having an empty microwave running.

There Are Some Exceptions For Using Aluminum Foil In A Microwave;

  • There are times when the foil is helpful in the microwave. For instance, when cooking chicken, there are portions you should cover to ensure they don’t overcook like the drumsticks. They tend to cook pretty fast, while the rest of the chicken cooks at a slower rate.
  • You can cover such portions with foil to minimize the amount of heat that reaches them. This, however, slows down the cooking time relative to other parts. The entire method can lead to arching, as foil can produce sparks if they come into contact with the turntable or the metallic walls.
  • Foods that come in aluminum containers labeled “safe for microwaving” are another exception. The manufacturer provides instructions on how you should use them. But, if the container is more than 2 inches thick, you should use a different container to ensure food is reheated properly.
  • Foil is also used in conventional microwave ovens during convection cooking. Still, it should not be set in the microwave when you’re microwave heating as it disrupts the cooking process, so food ends up cooking unevenly.

Substitutes You Can Use Instead Of Aluminum Foil;

  • Parchment paper – ensures even food heating, unlike foil, as it has great heat-sealing properties.
  • Wax paper – is also used as an alternative, but it wouldn’t be a great option if you’re coking fatty foods or those which can easily burn.
  • Plastic wrap – it is microwave safe, making it an excellent substitute. However, it should never come into contact with the food since it can produce toxic substances when working with high temperatures.
  • Another substitute for aluminum foil is any container labeled “microwave safe.”

Here are some very helpful safety tips;

  • Never put recycled foil in the microwave because wrinkled foils cause sparks.
  • Since foil covers only a quarter of the, you can save the rest because you might need it to cover some parts of the dish to prevent them from burning or overheating.
  • You should not place large plates in the microwave with aluminum foil because there’s a high possibility of the foil touching the metallic walls. This can easily damage your microwave. 

See also: Best 5 Microwaves With Rotisserie In 2023 – Reviews


Is it safe to use aluminum takeout containers in a microwave?

It can be very unsafe to put aluminum containers in a microwave because they can damage it or start a fire. You can put the leftovers in a microwave-safe dish when reheating them.

Can you reheat food using aluminum foil?

You can, but the food barely heats up when using aluminum foil.

You can try plastic Foil- food heats up uniformly and gets hot. It will help if you are careful when eating it to avoid burning your mouth.

Why does foil produce sparks when in the microwave?

If you’re using something metallic in the microwave, charges begin to move around. If it’s a thin metal like aluminum foil, voltage tends to build up, exceeding the voltage of air, causing a spark.

Is there a toxic side to aluminum foil?

Aluminum foil features a shiny and dull side, and most people say the shiny side should be on the inside and the dull side on the outer part, but you can use either side.

Can you eat food that is reheated using aluminum foil?

Yes. Reheating food while folding it with aluminum foil increases the quantity of aluminum in the food. The amount is small, though, and researchers say it’s safe. 

Final Verdict

You can put Aluminum foils in microwaves, but it has its benefits and limitations.

Always follow the manufacturer’s instructions keenly if you have to use foil in a microwave.

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I am a professional appliance repair expert and write articles that help average users diagnose and troubleshoot their kitchen gadgets, like microwaves, dishwashers, etc. I’m a foodie by heart and love reviewing food recipes, ingredients, and the cookware products used in them for meal preparation.