can you put pizza box in microwave

Is It Safe To Microwave Cardboard?

What do you think; is it safe to microwave cardboard? Considering the nature of cardboard it is a fair question to ask as they are a fast conductor of fire. However, it should not be a problem with most home appliances. I know now that you have tons of questions to throw at me, but reading the full article will help you get perfect answers to all those questions. Let’s get started.


Is Cardboard Good For Food Packaging?

Well, 50% of food products use cardboard as packaging; that itself provides the answer to this question. Cardboard food container boxes have numerous advantages to the food industry. With them, the shelf life of food ingredients gets increased, and the structure of the packaging keeps the food fresh and safe.

In addition, using cardboard carton boxes for food items reduces waste as well. In fact, there are more pros of cardboard than cons when it comes to food packaging; let’s keep them for a separate article.

What Type Of Cardboard Is Used For Food Packaging?

There are different types of cardboard materials, and manufacturers use them according to their packaging requirements. However, the white board is the most used one out of the lot, particular as the inside cardboard of the boxes.

White board is typically made of a few thin layers of bleached chemical substances, and people use wax or laminate on white board to seal the heat inside the cartons. Moreover, it is the widely regarded form of cardboard for direct contact with food items. 

What Does Microwave-Safe Mean?

Simply put, it says the material is safe to use inside of a microwave. Since I’m talking about cardboard in this report, microwave-safe cardboard won’t get melted or create fire when you use it as a microwave box.

Further, such materials have no impact on the food you cook. There will be no chemicals transferred to the food from the cardboard containers. 

Is Microwave Safe For Health?

Perhaps, you would feel this is irrelevant to the topic we discuss. However, note that cooking in the microwave is perfectly okay and has no issues to the health; at least that is what experts have to say with this regard. Microwaves work with low-frequency electromagnetic radiations to cook food, which is considered harmless to the human body.

How does microwave warm up cardboard?

Is It Safe To Microwave Cardboard?

Yes, generally speaking, there should be no issues with microwaving food on cardboard. If you ask, is cardboard microwave safe? I would say it’s better to read the instructions of the manufacturer rather than trying whatever cardboard you get your hands onto. Most cardboard food containers (as an example, pizza containers) says they are ok to microwave food. 

I strongly urge you not to microwave whole foods box when manufacturer specifically have advised not to do so. In such situations, remove them from the box and use a microwave-safe pan for the job. 

Even when you see the green light of the manufacturer, it would be best if you microwave cardboard box containers for shorter periods of time. As I said, cardboard is a quick conductor of fire and leaving it unattended for long periods in a microwave can be catastrophic. 

It is very unlikely to cause a fire if you stick only with microwave-safe cardboard, but prevention is always better than cure. Furthermore, it will lead to making waxed dirt in the microwave if you cook for extended periods. 

Also, it must be mentioned that you should stay away from using cardboard packaging that consists of substances such as ink, glue or wax (unless the manufacturer advised doing so). 

How Does Microwave Warm-Up Cardboard?

In order to understand the answer, first, you have to understand the mechanism used in a microwave. As I said, a microwave cooks food with electromagnetic waves, and these waves absorb the moisture, fat and sugar from the inside objects, be it food or cardboard. 

The rotating molecules of the food tend to generate heat when they meet other molecules, and that heat gets transferred to the cardboard as well. The electromagnetic waves of the microwave can absorb certain components of plastic and cardboard; that is why you always should use microwave-safe objects inside a microwave.

Do cardboard boxes hold heat? Yes, they do as long as they are made of microwave-safe material. 

How Long Can You Microwave Cardboard?

This is a good question to answer. Like I mentioned earlier, it is better not to microwave cardboard containers for longer periods. But, what is the exact time? I would say you should not exceed two minutes.

Ideally, try the time span of around one minute. For those who want an extended microwave time, it is a must to take short intervals after every one minute; the break should be at least 30 seconds as well. 

Tips to Microwave Cardboard

I have already shared some crucial tips with you how to handle cardboard safely in the microwave. Let me bring them down to one place.

  • First of all, make sure the cardboard is microwave-safe. You could inspect this on the packaging and do not get tempted to use cardboard packages if the manufacturer did not approve.
  • Do not leave cardboard containers in the microwave for more than two minutes. For longer durations, break up the process every minute, leaving at least 30 seconds of rest time.
  • Don’t put cardboard containers without food. Microwaves absorb the moisture pretty fast, and the moisture content of cardboard tends to get vanished in no time when there is no food in the box. 
is cardboard microwave safe

Can Cardboard Set On Fire In The Microwave?

As I mentioned, it is highly unlikely for cardboard to catch fire in a microwave as far as you are using microwave-friendly containers to heat the food. Still, it is not advisable not to leave cardboard food containers without food.

The fast moisture evaporation process will lead cardboard to catch fire if you allow it in the microwave for too long. In addition, scrunched up cardboards are prone to ignite faster than the others. All in all, they are safe as long as you keep the hazard in mind! 

Instances When Cardboard Shouldn’t Be Microwaved

Most cardboard packages come with decorated ink and wax on them, and they cannot be approved to use in the microwave. However, it all depends on the comment of the manufacturer. So, read the label first and decide on that.

Moreover, glue is another factor that requires eager attention. Packages with glue on them can cause the glue to transfer to the food when you microwave. 

Foods And Drinks You Should And Shouldn’t Microwave With Cardboard

If you are building a myth that microwaving cardboard is dangerous, I need you to get rid of that mentality. Generally, there is nothing to worry about microwaving cardboard containers. However, nowadays, literally, every food product comes with cardboard packages. So, I want you to say no to the following list of foods with cardboard containers.

  • Grapes
  • Eggs 
  • Dried peppers

Pros & Cons of Microwaving Cardboard

Every story has two sides to it. Here are the pros and cons of a cardboard box microwave.

Pros of cardboard microwaving

  • Cardboard packages have less amount of moisture in them. It helps to speed things up to limit the cooking time.
  • You don’t have to look for microwave-safe pans or trays if the cardboard container is microwave-safe. 
  • No mess of cleaning additional stuff.
  • No harmful substances are in microwave-safe cardboard containers to make you sick.

Cons of cardboard microwaving

  • You cannot microwave for longer times if you put food in cardboard containers.
  • Cardboard is a fast conductor of fire. If left unattended, you could end up with fire. 
  • Not all cardboards are microwave-safe. If you accidentally put such packages inside of the microwave, harmful substances can get injected into food.


Do you still have unsorted questions? Then this section of the article will help you out with answers to some frequently asked questions regarding “is it safe to microwave cardboard?”

Can You Put The Pizza Box In The Microwave?

Yes, in most circumstances, it should be safe to put pizza boxes into the microwave. However, as I kept saying throughout the article, the compatibility is mentioned on the pizza box by the manufacturer. So, don’t just rely on my answer; it’s better to read the label. Also, you can use a microwave cardboard shield to keep everything on the safe side. 

Can You Microwave Chinese Takeout Containers?

As far as the container is made of glass or ceramic, you can use them in the microwave. As you would assume, the Chinese takeout containers are safe for microwaves. However, if the containers have metal parts, they should be removed before you put them in the microwave. 

is it safe to microwave cardboard

Can I Put Dominos Cardboard In Microwave?

Regardless of the brand of pizza you have ordered, read the instructions of the manufacturer before you put any object to the microwave. Yes, you should be able to microwave Domino’s pizza boxes as they are compatible with doing the job. That said, keep the inner time below two minutes.

At the end of the day, they are cardboard-made boxes, and you can’t expect them to last long under high temperatures. 

Are McDonald’s Boxes Microwavable?

McDonald’s cardboard boxes are made of carton board, and they are free of metal or plastics, making them suitable for microwaving. Moreover, these boxes are considered microwave-safe; hence using McDonald’s boxes for microwaving shouldn’t be an issue.

But, there can be special cases where they specifically mention that the packages are not ideal for use in the microwave. So, it’s the same theory again; read first and do accordingly. 

Can Cardboard Coffee Cups Be Microwaved?

If you are asking me about the ordinary paper coffee cups, I’m afraid, no, you can’t microwave them. Most of them are made of thick paper and contain glue that keeps the cup intact. As we discussed, the microwaving process will melt the glue to the coffee and most importantly, microwaving paper is not something you should be doing.

This answer is for ordinary coffee cups that we buy day in day out. Still, that is applicable for cardboard cups as well, simply because of the glue. 

Can You Microwave Cardboard Takeout Boxes?

As we know, cardboard is a byproduct of wood fiber, and generally, cardboard takeout boxes are safe to put in the microwave. The deciding factors are wax, ink and glue on the packages. If you notice such stuff on the box, please do not proceed with the microwaving.

Also, it won’t take more than a couple of seconds to read the label; it will have whether it is appropriate for the job or not.

Is It Safe To Microwave Cardboard?

Although we reached the conclusion of the article, my answer to this question would be yes and no. As I explained, most cardboard food containers are microwave-safe, but if you can’t figure out any instructions on the label, I recommend you not go ahead with microwaving such containers. Have a great day!

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