Can You Put Cardboard In The Oven? (Detailed Explanation)

Here’s the thing, we live in a world where people are keen to find new and also exciting ways to save themselves time and money – because let’s be real, we are all super busy.

We live in a world where society is constantly busy, so if we can cut corners or get a quicker result, we are usually all about this.

Can You Put Cardboard In The Oven? (Detailed Explanation)

This is what we are here to talk through today – a question that not many people can give a well-evidenced answer to is: can you put cardboard in the oven?

You will be surprised at how often this question gets asked – and you might be even more surprised to learn that the answer is not a simple YES or NO.

The truth is, whether or not you can put cardboard in the oven depends on a whole host of factors – so here we are going to break down what situations will allow you to put cardboard in the oven, and what situations will make this a pretty awful idea.

On the whole – putting cardboard in the oven is not something that can be recommended, because it is a fire hazard.

However, we are going to break down all things about putting cardboard in the oven, and why doing this is not the best idea.

Let’s Talk About Cardboard

It is really important to understand the fundamental facts about cardboard – the first one being what exactly cardboard is made of, and how exactly cardboard is made.

This is what can really give you the evidence behind why you should not torch cardboard.

So, cardboard is made by pressing layers of paper together. This is something that is done with glue or with another kind of adhesive.

You will probably recognize cardboard for being pretty affordable, and also lightweight, and yet sturdy. This material is definitely multifunctional, although we take it for granted as being used to deliver goods.

However, just because this material is super cheap – does not mean that it isn’t great for the planet.

Cardboard is a material that can be recycled, and this is something that you should make a conscious effort to do.

You can really help the environment by recycling cardboard in the right way – but this is something that we will really get into later on.

It is important to mention that the only kind of cardboard that can’t be recycled is cardboard that has been exposed to chemicals or that has paint applied to it.

If this was the case, you would not be wanting to use this cardboard in the oven either… 

Does Cardboard Have An Ignition Temperature?

Before we even discuss the answer to this question, it is important to establish what exactly the term ignition temperature means. 

So, ignition temperature is the lowest temperature at which something will catch fire. How does this work? Well, the higher that the ignition point is then the more easily that it will catch fire. 

The majority of cardboard is actually made out of recycled paper, and this means that baking it in the oven is not the best idea.

The heat can end up causing the cardboard to catch fire and the flames could end up spreading to your food.

Also, the fumes that come from the burning cardboard are not exactly safe… So this is something that should really be avoided.

Ultimately, you really should avoid baking anything on top of any sort of cardboard box or sheet.

That’s right, even if the cardboard has not been treated with dangerous chemicals and even if it does not have paint applied to it, it just is not a good idea.

This is something that could ultimately lead to a fire breaking out, and this could seriously compromise your kitchen.

In this situation, you really need to take a step back and ask yourself: is it really worth the risk? This would present you with a resounding no as an answer.

Does Cardboard Have A Solid Ignition Temperature?

So, this is a question that does not have one answer. Whether or not this question can be answered really depends on the cardboard you are dealing with.

There is a lot to think about when it comes to establishing the ignition temperature of something.

That’s right, you have to take into consideration how thick the cardboard is, you also have to consider whether or not the cardboard has any coating.

You also need to be aware of whether or not the cardboard has been subjected to any chemical treatment.

Being Safe In Your Kitchen

Being Safe In Your Kitchen

So, obviously, we are here to help you and to work out if there are any kinds of situations where it can be safe to put cardboard in the oven.

We can’t say that it totally is or that it totally isn’t. The way that we get to this verdict is slightly confusing. 

You will be familiar with fire safety rules and regulations, and so you will know that you should really avoid putting any kind of cardboard in the oven.

That’s right, even if the cardboard has not been treated with any dangerous chemicals, and even if the cardboard does not have any paint applied to it – you really should not put it in the oven. 

This is because of the way that the heat will react with the cardboard itself. Ultimately, the heat will cause the cardboard to ignite, and the flames could end up spreading to your food.

In addition to this, the flames will give off toxic fumes that are unsafe to breathe in.

If you are trying to find a useful way to reuse your cardboard boxes, then you should really reconsider using them in the oven.

Here’s the thing, there are a lot of other ways that you can reuse and recycle your cardboard supply because it is a really multifunctional material source.

You really should not try and save the environment by putting yourself at risk.

Why Would You Want To Put Cardboard In The Oven?

You might be reading this and really questioning why someone would want to consider putting cardboard in the oven – this might be something that seems totally illogical to you.

However, the main reason behind this is pretty environmentally friendly. People will be wanting to do this in order to recycle their cardboard.

And, they might not know if it is really safe to do so. That’s why we are here!

We all view cardboard as a pretty basic material, but it is super deceiving. That’s right, there is more to cardboard than just boxing up your online orders.

Cardboard is a super versatile material, and it can be used in a lot of different ways.

The reason why you’re probably here is that you are wanting to use your cardboard as a kind of oven liner and this will stop contents from sticking to your dish.

However, cardboard might not be the most reliable source for this. We say this because the cardboard might not be able to withstand the heat, and this will ultimately create a huge mess for you to tidy.

Depending on what you’re cooking you might want to use aluminum foil instead. 

Can You Really Put Cardboard In The Oven?

Here’s the thing, you can actually put a sheet of cardboard on an oven rack or on top of any baking dish which is in the oven.

When or how would you do this? So, this works especially well on baked potatoes and casseroles – or even cornbread.

This is something that will massively improve cooking time too due to the fact that the cardboard will absorb some of the heat.

You will be pleased to know that cardboard can actually be cut in order to fit any size dish, and for this reason, you will not have to worry about wasting materials.

However: just because you can put cardboard in the oven, does not mean that you should. Sure, technically you can put cardboard in the oven, but this is not something that is safe or recommended.

To outline this further, we need to explore what exactly happens when you put cardboard in the oven.

What Happens When Cardboard Goes In The Oven?

It is true that the majority of cardboard will be made from recycled paper, so it is not a good idea to put this in the oven.

This is due to the fact that the heat can make the cardboard ignite and this might spread to your food, or, go forbid, your home.

For this reason, you need to avoid baking on any kind of cardboard sheet or any kind of cardboard box, as it just is not a good idea.

The last thing you want is for a fire to break out in your kitchen, and for you to put yourself at risk just to try and save the environment.

There are other ways that you can recycle cardboard that do not need you to risk starting a fire. 

Putting any kind of paper source in the oven is a really bad idea. In fact, even putting wax paper in the oven can give off some really dangerous fumes.

These can waft right through your kitchen, and this is not something that you want yourself or your family to endure.

It’s Really Not Worth Testing Your Cardboard’s Limit

It’s Really Not Worth Testing Your Cardboard’s Limit

We have no idea what kind of oven you have, however, it is not wise to test out the heat of your oven on cardboard.

The tolerance that cardboard has to the temperature of your oven will not be great – and for this reason, you should consider using a different material such as aluminum foil.

Trying to put cardboard in the oven might save you time or might feel resourceful to you, but ultimately this is something that has a lot of risks and will pose serious danger to your kitchen.

Can You Actually Microwave Cardboard?

Here’s the thing, there are some paper products which are not suitable for microwaving and this is due to the fact that they contain wax or different coatings which could catch fire when heat is applied to them.

We don’t recommend microwaving a sheet of cardboard because this could cause it to catch fire – you need to be super careful if this is something you are wanting to do.

There are a lot of other safer materials out there that can be microwaved, and that do not cause such a huge fire risk.

Why Should Cardboard Never Go In The Oven Or In The Microwave?

So, we have established that putting cardboard near any kind of heat source is pretty dangerous because it is made from paper.

Not only that, but you need to take into account what kind of cardboard you are dealing with and how much you know about its history. 

For instance, if you are unfamiliar with the previous life which the material used to make the cardboard had, then it is sensible to avoid putting it close to a heat source. 

What is the main reason for this? Well, this is all to do with chemicals and paint…

Let’s Take A Look At Cardboard And Toxicity

So, in order to think about toxicity in relation to cardboard – we really need to think back to how the traditional paper products are actually created.

It is true that traditional paper products are actually made from pulped wood fibers or even from recycled newspaper – or maybe even recycled junk mail.

This is something that gives us an especially good indication as to why individuals will use painted or treated cardboard boxes.

If you are not sure whether or not your cardboard has been treated then this is something that you need to avoid using in your oven. It is just not worth the risk.

Can Cardboard Slow Down Cooking Time?

You will not want to put cardboard in the oven because it can end up slowing down the cooking process. Using something like aluminum foil will not have this effect.

Why? Because it is all about the material. Aluminum foil is reflective, so this means that it will reflect the heat right onto your food, which will make your food cook a lot quicker than if you were to use cardboard. 

Cardboard is not just a health and safety hazard here… Cardboard is literally slowing down the cooking process, which renders using it pretty pointless!

So, if the whole being unsafe thing didn’t convince you to not use cardboard, then ultimately learning that cardboard prolongs and worsens cooking time should be enough of a game-changer to make you reconsider.

Would Using Cardboard Affect The Taste Of Your Food?

Would Using Cardboard Affect The Taste Of Your Food?

So, aside from putting cardboard in the oven being totally unsafe and counterproductive… It can actually make your food taste strange.

That’s right, cardboard will give off an unpleasant aroma as well as the fumes from burning, and so this is what will make your food taste really gross.

This is not even an experiment or an experience that you should consider entertaining or attempting…

Using cardboard in the oven will not save you time, it will not be safe – and on top of that, it will just make your food taste really weird. 

Whatever you have in the oven will come out tasting disgusting and all your hard work will just be a huge waste of time.

Sure, it is good to help the environment and make a conscious effort to reuse materials… But this is in no way a safe or a sensible way to reuse cardboard.

We would even go so far as to say that we have given you sufficient evidence as to why cardboard should NEVER go in the oven.

But What About Takeaway Pizza?

Here’s the thing, even though takeaway pizzas come in pizza boxes – this does not mean that they are suitable to be baked or reheated in the oven by using these.

The purpose of having a cardboard pizza box is so that it can be a protective layer for the pizza. The cardboard box will be absorbing any kind of grease or any kind of oil that could leak out of the pizza.

Ultimately, the cardboard box is the means of your delivery driver transporting the pizza from the pizza shop to your house. 

However, just because pizza comes in a cardboard box does not mean that this is a suitable receptacle to reheat your pizza in.

Ultimately, it would be really dangerous to try and bake a pizza on top of a cardboard base – so reheating would have the same complications and repercussions. 

This is because the cardboard would burn and this would affect the taste of the pizza and also give off some gross fumes.

If you choose to do this, then you are putting yourself and your pizza in a super dangerous situation. 

Why You Shouldn’t Reheat Your Pizza In The Cardboard Box

As we have mentioned before, cardboard can catch alight if it hits a certain heat (this can be different depending on the cardboard) so this makes reheating pizza in your cardboard box a really bad idea.

It is important to note that the type of oven that you have can also have an effect on this. The type of oven that you have can heighten or it can lower the chances of your cardboard catching fire. 

If you have an older oven, then you will find that this will have a much older element, and this is much more exposed to the inside of the oven. For this reason, the fire risk is massively increased.

Why isn’t this the case for newer ovens? Well, their heating elements are covered much better, and they circulate the heat – this is what makes fire risk less likely.

However, this is NOT a green light for you to test this out. No matter whether you have a really new or a really old oven, you still should not try to put cardboard in there.

Cardboard Prolongs Cooking Time Massively

You might be fooled by the myth that leaving your cardboard on your pizza will end up saving you time, however, this is totally wrong.

Yeah, leaving the cardboard on the bottom of your pizza that you get from the food store will be a huge cooking barrier. Not only will this slow down the cooking of your pizza, but this will also prevent your pizza from being super crispy.

It is important to mention that there are some foods that do require staying in their paper or cardboard trays to be cooked – the most common example of this is frozen dinners.

These come in cardboard trays which are made specifically to withstand and cope with the heat of the oven.

Ultimately, if you are working with a paper product that has not been designed to go in the oven, then this is not something that you should consider.

For the sake of an extra few seconds to disregard and dispose of the cardboard that is not suitable for the oven, your home and the local fire department will thank you.

That Smokey Flavor

You might find that if you keep the cardboard on when you cook your pizza that you won’t just get a smokey flavor… It’ll be a pretty burned flavor.

Not only will the smoke from the burned cardboard make your pizza smell and taste gross, your oven and your kitchen will also smell pretty gross.

Would you leave plastic on your food that’s going in the oven? No! So, why would you leave cardboard on your food?!

There really aren’t any benefits to leaving cardboard or other kinds of packaging on the food you’re putting in the oven – so it is not worth the risk.

So… How Do You Reheat Pizza Without Using The Cardboard?

So… How Do You Reheat Pizza Without Using The Cardboard

As we have already mentioned, just because takeaway pizza comes in a cardboard pizza box does not mean that it should be reheated in this.

This is because the cardboard pizza box can easily catch on fire if it is exposed to heat.

However, if you have a microwave then this would be a suitable way to reheat your pizza – without the pizza box.

You will only need to microwave your pizza for a few seconds, or if you’d prefer, then you can reheat it in the oven. This will take five minutes to do.

You can also reheat your pizza by using a skillet, and this needs to be done on medium heat – but you will need to make sure your pizza is hot and crispy before you take it out.

You could even use your toaster oven as a way of reheating your pizza. However, you need to make sure that you preheat the toaster oven and then bake your pizza for ten minutes.

Have you bought into the air fryer craze? Well, you can also use this to reheat your pizza – this will take a couple of minutes and your pizza will be reheated and perfect to eat. 

However, all of these methods will require you to supervise your pizza while it is being reheated because it might take less time than you are expecting to reach perfection.

Why You Do Not Need Cardboard

There are actually a lot of different ways that you can eradicate that weird need to keep the cardboard on your food when you put it in the oven.

Ultimately, if you are cooking frozen pizza, you should just listen to the heating instructions on the packaging. If you are reheating leftover pizza, then you can use a cookie sheet to reheat it.

Why use a cookie sheet? Well, this will mean that the metal can heat up evenly and this will cook and crisp up the bottom of the pizza.

In addition to this, a cookie sheet can be a really great option for other frozen foods too. That’s right, you will find this to be a pretty great baking solution – you’re welcome!

The cookie sheet will not be a fire risk, and it will allow you to perfectly cook your frozen foods, or it will allow you to reheat your pizza pretty nicely.

Alternatively to this, you can use a casserole dish or even a baking pan to reheat or to cook your frozen foods.

The thing is – a casserole dish is not ideal for cooking pizza, it will be more effective for cooking other kinds of food – but it can still work.

In addition to this, if you have aluminum foil and nothing else to cook your pizza on, you can just cover the oven rack with aluminum foil.

However, this is something that you should do before you preheat your oven because you do not want to risk burning yourself.

Also, if you are conscious about wasting foil then you can just cover the middle part – and this is a great alternative to cookie sheets.

Should You Invest In A Pizza Block?

This depends on how much of a pizza lover you are… If you are someone who eats a lot of pizza, this might be a worthwhile investment for you.

You might not know what a pizza block is, but this is basically a specially made ceramic sheet that you put directly into your oven in order to cook your pizza on. 

The purpose of a pizza block is to stop the cheese from dripping right into your oven, and this in turn makes the crust really crispy.

In addition, a pizza block can also be used as a way of baking other kinds of frozen foods. For example, you are able to put burritos on a pizza block to bake them. 

No matter what food you like, you will find that a pizza block can make it super crispy and delicious.

Know What Can Be Baked Directly On The Oven Rack

You will find that there are some foods that can actually be baked directly on the rack. For example, if you are making pizza, then you can take the cardboard from the bottom of the pizza, and you can just put the pizza straight on the rack. 

In addition to this, if the food that you are making has an oven-safe container, then this is something that you can normally put straight on the rack.

Moreover, putting food directly on the rack will be an especially suitable approach if you do not have any other alternative method. 

However, if you are doing this with pizza, then you might encounter the risk of cheese or even of the pizza toppings dripping down to the bottom of your oven.

If you are tempted to leave the cardboard at the bottom of your pizza then you should consider using an alternative method to cook it – but we can’t stress enough that you need to avoid the cardboard option.

This will reduce the risk of a fire and this will make your food cook so much better too.

The Benefits Of Using Parchment Paper To Reheat Pizza

Another option that you can consider trying is using parchment paper to help you reheat your pizza. This is the perfect option if you are keen to find an alternative to cardboard or aluminum foil. 

What is parchment paper? This is an especially thin paper, and it is also a non-stick paper that is used in baking.

However, it is important to mention that non-stick parchment paper can be used in the oven and also in the microwave.

This is a multifunctional kind of thing, as it can really help stop your pizza from sticking to a baking sheet or to a baking dish. 

How should you use it? Well, when you are reheating your pizza, you should put it right on top of a piece of parchment paper.

Once you have done this, you can put your pizza in the oven, or you can then put it in the microwave. This is a really good way to just ensure that your pizza remains crispy and that it does not become soggy. 

In addition to this, parchment paper is super easy to clean, and it can also be reused many times.

What About Using A Pizza Pan Or A Pizza Stone?

What About Using A Pizza Pan Or A Pizza Stone?

If you are especially keen to really boost your pizza reheating game, then you should really consider using a pizza pan or a pizza stone.

It is true that both a pizza pan and a pizza stone are designed so that you can reheat and also cook your pizzas to perfection.

They are an especially amazing option if you are keen to get that unique and authentic tasting pizza.

How do you reheat pizza by using a pizza pan or a pizza stone? You need to put the pizza on top of the preheated pizza pan or the preheated pizza stone.

You can then cook or reheat your pizza. Using your pizza pan or your pizza stone is the best way to achieve the perfect pizza crust. 

Let’s Talk About Recycling Cardboard

It is really important to remember that cardboard and other packing materials can be recycled in a lot of different ways.

It is critical that you check with your local recycling center, just so that you know what kinds of cardboard they can accept.

It is true that the majority of recycling centers will have a system where they will actually recycle the cardboard and this will be made into new cardboard boxes.

There are actually a whole lot of possibilities for recycling old cardboard boxes and also packing materials. Do not just throw your cardboard in the trash; make sure that you recycle it.

We all constantly get online shopping deliveries that come in cardboard boxes, so this is why it is super important to recycle your cardboard boxes.

Get in touch with your local recycling center and find out what their conditions are.

For instance, some recycling centers will not accept stickers on cardboard boxes because they are not recyclable.

Just to be on the safe side, you should take off any stickers, so then you know that the cardboard can be recycled.

Making Your Own Boxes From Recycled Materials

It is also important to mention that you can also make your own boxes from recycled materials. If you are wanting creative control, then you can make your own boxes and packing materials that are even more environmentally friendly. Result! 

In addition to this, you will be able to buy fun colored papers so that you can make your cardboard packaging super pretty. 

So, what are you waiting for?! Make your own cardboard boxes and packaging out of cardboard that would otherwise be recycled.

This is a super fun and innovative way for you to show how much you care about the environment – and if you have your own business or your own organization, then this is a great USP.

You might not be really into craft, and for this reason, you will be able to find alternative ways to source cardboard boxes from your recycling center.

In case it wasn’t totally obvious, there are a whole lot of possibilities for old cardboard boxes. You can recycle and reuse them, and they can be used as packing materials.

The bottom line? Do not throw them away – recycle the cardboard boxes.  

In Conclusion

Overall, putting cardboard in the oven is not a safe or sensible idea. This is because the cardboard can very easily catch fire – and not only that, but the fumes from burning the cardboard are toxic and dangerous to breathe in. 

Ultimately, the threat of spontaneous combustion and the cooking time slowing down, along with making your food taste weird, are just some of the reasons that would make putting cardboard in the oven a pretty bad idea.

Cardboard should not even go in your oven if it is just on warm, because even if the oven is not red hot, the heat will still make the cardboard release fumes.

There are a lot of different ways that you can recycle and reuse cardboard, you do not have to put it in the oven as a means of doing this.

You can reuse cardboard in order to make alternative packaging methods, and this is especially useful if you have your own business.

This would really help you leave an environmental mark on the market, as well as encasing your products in super high quality packaging.

In addition to this, you can also recycle pizza boxes. However, they can’t be recycled if they have grease on them or if they have food residue from the box.

This is because some recycling centers will not accept cardboard that has been contaminated by food. 

You could check with your local recycling center whether or not they accept pizza boxes or whether or not they have a separate bin that can be used for recycling and disposing of pizza boxes.

As we have mentioned throughout this piece, heated cardboard can actually release toxic fumes. For this reason, it is not recommended that cardboard should be heated in the oven.

It is safe for you to recycle cardboard or to compost cardboard that has not been exposed to heat.

We have also explored how cardboard is biodegradable, and how it can actually be composted or recycled into new cardboard boxes.

You need to really make sure that you remove grease or food residue from cardboard boxes before recycling them.

Is anyone stopping you from putting cardboard in the oven? No… Does it mean that you should put cardboard in the oven?

Also no… There are a lot of other ways that you can reuse and recycle your cardboard without putting your health and your safety at risk.

You can be environmentally conscious in the safest possible way, you do not have to flood your kitchen with toxic cardboard fumes in order to save the environment.

That, and doing that totally defeats the point of saving the environment… 

Kunal Sharma
Latest posts by Kunal Sharma (see all)