Can Cardboard Go In The Oven? How To Do It Safely And Alternative Methods

logo by Editorial Staff | Updated on August 3rd, 2022

Can you put cardboard in the oven while it’s on? Do you want to place your leftover pizza in the oven with its cardboard box in the hopes of warming it? I wouldn’t do that unless you want to risk starting a fire in your oven. In this essay, I’ll explain what happens when you put cardboard in the oven and why it’s a bad idea.

Is it safe to put cardboard in the oven? Cardboard does not catch fire unless it is heated to temperatures over 400°F. While it is possible to keep the oven temperature below 400°F, placing cardboard in the oven while it is on is not recommended.

baked pizza

If the cardboard comes into contact with or is even close to the hot heating element in the oven, it might quickly catch fire. Some cardboard also contains combustible compounds that might ignite at a lower temperature.

It’s tempting to put a delivered pizza in its cardboard box in the oven to heat it. Even at temperatures below 400°F, this is a horrible idea. In addition to the causes described above, oil from the pizza box might cause the box to catch fire at lower temperatures.

Continue reading to discover more about putting cardboard in the oven, what happens if you do, and why it’s not a good idea.

Can cardboard go in the oven?

While many people claim to have done so, heating cardboard in the oven is not a good idea. Cardboard is made of paper, which is highly flammable. As a result, it can easily catch fire when exposed to high temperatures for several minutes.

If you have no choice but to heat your pizza in its cardboard box, keep the temperature at a safe limit of 170°F for the shortest amount of time. Consider other, safer methods of reheating cold pizzas.

Is it safe to put cardboard in the oven? Unless heated to more than 400°F, cardboards will not burn. Certain types of cardboard, however, contain flammable chemicals. And you won’t know if the cardboard you want to use in the oven contains these chemicals.

You should also remember that pizza contains oil and other greasy ingredients that can splatter on the cardboard box. When exposed to high temperatures, greased and oil-soaked paper can easily catch fire. If you heat the pizza in its grease and oil-filled box and then turn the temperature up to high, you risk starting a fire inside the oven.

Is it safe to put frozen pizza cardboard in the oven?

Putting frozen pizza cardboard in the oven can be dangerous. Put your pizza on parchment paper for a quick and easy way to heat it! This will keep your crust crispy and not soggy from cooking directly on the cardboard- especially if it is still cold when it goes into the Oven.

Cooking with cardboard isn’t always a bad idea. Consider the Pizzacraft Pizza Boxes! Cooking with these specially designed boxes may persuade even the most adamant non-cardboard users that there’s more to them than they thought.

You already know the answer to the question, “Can you put cardboard in the oven?”

It is not recommended to heat pizza in its cardboard box.

Did you ever wonder why pizza comes in cardboard boxes? Aside from the fact that they are convenient, the design of these boxes keeps the pizza warm. Of course, if you leave the box at room temperature for several hours, the pizza inside will become cold.

Consider why it is not recommended to heat pizza boxes in the oven: paper can quickly catch fire when exposed to extremely high heat. Some cardboard boxes are made primarily of recycled paper. As a result, they can easily catch fire. The majority of cardboard is made by gluing together several pieces of paper. Glue burns quickly as well.

Another reason is that heating the pizza inside its cardboard box will ruin its flavor. Most pizza boxes are made of thin layers of paper that easily heat up. Certain chemicals are also present in this thin layer of paper.

If this layer of paper burns, the pizza will have a bitter taste. Your pizza will also have a cardboard odor. The cardboard material, as a result, heats up faster than the pizza. As a result, if you place the box inside the oven to heat the pizza, the pizza will not be heated evenly.

Reasons Why Cardboard Should Never Be Used in the Oven

Pizzas aren’t the only things that come in cardboard boxes. Most frozen foods are packaged in a cardboard box with a plastic cover.

As a result, before baking your food, ensure that all packaging has been removed completely. Otherwise, you risk getting melted plastic on your food, which no one wants.

You should never put cardboard in the oven, no matter what you cook. This is why.

1. The Danger of Unintentional Combustion

The cardboard can catch fire if it reaches 427 degrees Fahrenheit. Most pizzas are baked at 425 degrees Fahrenheit or higher. This two-degree difference is far too close for comfort.

One of two things will happen if you cook your pizza while it still has the cardboard. Nothing will happen to your crisp and delicious pizza. Otherwise, the cardboard will smoke horribly and even catch fire, ruining your night and pizza.

The type of oven you use can significantly increase or decrease the likelihood of your cardboard catching fire. Heating elements in older ovens are more exposed to the inside of the oven, increasing the risk of fire.

Newer ovens cover the heating elements better and circulate the heat more effectively, reducing the likelihood of a fire. However, just to be safe, don’t do it.

And while it’s unlikely that your cardboard will catch fire, the mere possibility of something catching fire in your home should give you pause.

2. Reduces cooking time

Although you may believe that leaving the cardboard on your pizza saves time, the exact opposite can be true.

Leaving the cardboard on the bottom of your pizza or surrounding it can slow down the cooking time and prevent the bottom of your pizza from becoming nice and crispy.

However, some items are designed to be baked with the cardboard on. Some frozen dinners, for example, include treated paper dishes designed to withstand oven heat.

Do not use any type of paper product that is not specifically designed for baking in the oven. Simply take the extra time to remove it. The fire department will be grateful.

3. Alters the taste of your food

Even if your cardboard does not completely burn, it can still smoke and emit fumes.

These fumes can taint your food and make your oven and kitchen smell bad.

In addition to cardboard, most frozen foods are packaged in plastic to prevent freezer burn. If you don’t remove the packaging and throw the whole thing in the oven, it can produce a foul odor/taste.

The plastic may even melt into your food, rendering it inedible. But don’t worry, it’s simple to avoid. Simply remove all of the packagings.

The small benefits of leaving the packaging on your food do not outweigh the risks. Remove the cardboard and other packaging materials unless it is intended to be baked.

What Is the Composition of Cardboard?

Cardboard is made by gluing or otherwise adhering layers of paper together. It’s a low-cost, lightweight, and durable material used in various applications.

But just because it’s cheap doesn’t mean it’s not recyclable! If you’re unsure whether you should recycle your cardboard boxes, this article can help.

As long as the cardboard hasn’t been treated with chemicals or painted (in which case the answer is no), anyone who wants to can bake their items directly on top of some cardboard in the oven.

Remember that some paper products cannot be microwaved because they contain wax or other coatings that may ignite when heated.

Don’t go too far and try to microwave a sheet of cardboard, as this could also cause it to catch fire.

What is the temperature at which cardboard burns?

At 427 degrees Fahrenheit, cardboard ignites (219 degrees Celsius). However, cardboard can smoke and smolder before it reaches that ignition temperature. For example, attempting to bake a pizza in the oven with cardboard on the bottom could ruin the pizza and the oven or even start a fire.

Can you put cardboard in a low-temperature oven?

Long story short, the safest strategy is to avoid placing any cardboard in the oven. Putting cardboard in the oven, even at the lowest temperature, increases the risk of spontaneous combustion or fire. Cardboard is made by manufacturers using a paper framework and a corrugated board.

Can I bake a pizza box at 175 degrees Fahrenheit?

In the Oven. You may keep your pizza warm in the oven in two ways: Pizza boxes will not catch fire until they reach temperatures exceeding 400 degrees. Set your oven to the lowest setting and place your pizza, still in its box, on the center rack. If you’re pressed for time, turn up the heat a notch.

Can cardboard spontaneously catch fire?

Spontaneous combustion occurs when a combustible item erupts into flames out of nowhere. It is, in fact, a chemical reaction that occurs under particular conditions.

According to the Handbook of Fire Prevention Engineering, “spontaneous combustion is a runaway temperature rise in a body of combustible material that originates from the heat created by some activity taking place within the body.”

When exposed to carbon-based animal or vegetable oils, such as cooking oil, maize oil, lard, or margarine, cardboard can spontaneously fire.

Is heated cardboard harmful?

Cardboard containers frequently include glue, wax coatings, or ink prints that might be harmful when heated with frozen meals. Chemicals from ink printing can contaminate your food and make it unhealthy to eat. In addition, when cooked or baked in cardboard, your meal may taste strange.

What Is the Use of the Cardboard Base in Pizza Packaging?

The cardboard base in pizza packaging is not intended to be baked in an oven. It is intended to be discarded once the pizza has been removed.

It acts as a food-safe barrier between the pizza and the plastic tray. The cardboard base absorbs any grease or oils that may leak out of the pizza, keeping them off the plastic tray and away from the next pizza that is packaged.

The cardboard acts as a barrier between the pizza and the metal bottom of the box, preventing the pizza from sticking to the metal and becoming mangled during transport. It aids in insulating the pizza and keeping it warm during transportation.

Furthermore, the cardboard protects the pizza from becoming wet or soggy due to contact with other food items in the box.

It would be risky to attempt to bake a pizza on top of this cardboard base, as it could easily catch fire. If you bake the cardboard base, it will most likely burn and emit toxic fumes. So, please, don’t! You’ll only be putting yourself in jeopardy.

So, don’t put your cardboard pizza box in the oven–not it’s designed for that! Instead, recycle it in one of the many other safe and environmentally friendly ways.

What to Use Instead of Cardboard in Baking Pizza

Finally, we know that using a cardboard box to bake food is not a good idea. Instead of cardboard, we can place some alternative baking goods here.

Baking Pan

Instead of cardboard, a baking pan may be the best option for baking. Various types of pizza pans are available on the market, especially if you want to bake pizza.

Each baking pan has its own set of advantages and disadvantages. As a result, you must purchase a round-shaped pizza pan because they are specifically designed for pizza.

Take a suitable baking pan for your food and place it directly in the oven.

The cookie sheet is another second method for baking food. If you don’t want to spend much money, get this baking sheet instead of a pizza pan. A cookie sheet, like a baking pan or a pizza pan, produces similar baking results.

Place your pizza or food on a cookie sheet in the oven without being tense. The baking sheet will not spoil food and will not catch fire.

Place directly on an oven rack.

This is yet another method of baking food directly on the oven rack. This method is very effective for certain types of food, such as pizza, because if you place your pizza directly on the oven rack, it will receive sufficient heat from all sides, including the bottom sides. Finally, the crust will be crisper.

Aluminum foil

Can you put aluminum foil in the oven? Of course, this is a common practice when wrapping food in aluminum foil for the oven.

If you want to be on the safe side, aluminum foil is the way to go because it does not catch fire.

Aluminum foil is useful for baking food in the oven, but it should be avoided when cooking at high temperatures. It should not be used with acidic foods.

Aluminum foil has many advantages, including that it heats food quickly and makes cleanup easier. It is also not necessary to clean your oven after use.

So, here are some tried-and-true methods for baking food in the oven.

Pizza Block

One type of ceramic sheet is a pizza block. Finally, you could directly place it in the oven to bake food.

This is especially useful for baking frozen food because it can provide heat from the bottom. The pizza block contributes to a crispy crust on the food.

How to Heat Your Cardboard Pizza Box in the Oven Safely

There are a few alternatives to using cardboard or an oven to heat your pizza, as I’ll demonstrate later. However, if you insist on heating it in the box, you should know how to do it securely.

First, preheat your oven if you’re heating the entire pizza rather than just a few pieces. The safest heating temperature range is 170°F–250°F.

You may leave the box in the oven for 10–15 minutes, but check it every few minutes. Take caution while removing it from the oven since the cardboard will get hot.

Is it possible to keep pizza warm in the oven for an extended period?

The pizza will stay warm in the oven for up to three hours. If the temperature is low enough, you can place the pizza box in the oven. Warming pizzas at 200°F is ideal, and if you want to use the box, maintain it at 140-150°F. You won’t have to worry about the boxes burning at this extremely low temperature.

Three Safe and Effective Methods for Reheating Leftover Pizza

Your guests did not finish all of the pizza you ordered last night, so you put the leftovers in the fridge. Cold pizza is tasty, but reheated pizza is even better. Here are the three best ways to reheat pizza.

1) Warm them up on the stovetop.

  • Heat the pan over medium-high heat.
  • Heat the pizza slices on the pan for a few minutes. Make sure the slices aren’t covered.
  • Next, add a few drops of water to the pan’s side.
  • Cover the pan and heat the pizza slices for a couple of minutes.

2) Microwave the slices to reheat them.

  • Place the pizza slices on an oven-safe baking sheet.
  • Set the microwave to 30 to 40% power.
  • Place the dish containing the pizza slices in the microwave for 45 seconds.

3) Return the pizza to the oven to reheat.

  • Preheat the oven to 350 degrees Fahrenheit.
  • Wrap the pizza in aluminum foil and place it on the middle rack of the oven.
  • Wait 10 minutes until the pizza is warm and the cheese has melted.

We’ve answered the question, “Can you bake cardboard?” Next, consider what other materials can and cannot be placed in the oven while it is turned on.

What Materials Can and Cannot Be Used in the Oven?

Using the wrong types of cookware in the oven poses a serious risk. As a result, you must be certain that the dish you place in your oven will not explode or catch fire. To that end, I’ve listed the materials that can and cannot be used in the oven.

Oven-Safe materials


Glazed ceramic dishes can be used in the oven. Use ceramic dishes that can withstand high temperatures without leaching chemicals into the food you’re heating or cooking.

Glazed ceramic pans are widely used in the preparation and baking of lasagna, quiches, and tagines. The majority of them are also oven-safe. Porcelain tableware can also be used in the oven. However, use porcelain sparingly, especially if it is intricately decorated. They should only be used for short periods of heating.

Unglazed ceramics can also be used. However, make certain that they can be safely used in the oven. There are earthenware types that can crack when exposed to extremely high temperatures. As a result, they cannot be baked.


Metal cookware is completely safe to use in the oven. Some of these metals have non-reactive properties, such as stainless steel, while others, such as seasoned cast iron, have reactive properties with protective layers. Both can be baked in the oven.

However, even if they are made of safe metal materials, non-metal parts should not be used in the oven. For example, a stainless steel pan with a plastic handle should not be used in the oven. However, if the plastic is oven-safe, it is safe.

However, if the non-metal part is only rated for 400°F, do not expose the pan to 450°F. Please remember that PTFE (nonstick) coated cookware should not be subjected to temperatures exceeding 482°F or 250°C.


Food-grade silicone cookware is ideal for baking and cooking in the oven. Silicone is a material that high oven temperatures cannot destroy. However, don’t go above that if your silicone cookware is rated for a specific oven temperature. Most silicone cookware can withstand oven temperatures as high as 400°F.


Glass cookware, especially borosilicate, is perfectly safe inside the oven. However, they are not resistant to temperature changes. They will break if subjected to sudden extreme temperature changes.

For example, don’t make layers of lasagna on a glass pan; place it in the freezer overnight, and then bake it in the morning. This will easily shatter the cookware into dangerous glass shards.

Glass cookware is classified into two types: borosilicate and soda-lime. Both of their manufacturers claim that they are safe to use in the oven. Just make sure to check the markings on your glassware to see if they are genuine.

Oven Materials That Are Dangerous


You should not put all wooden dishes in the oven. Some of them may not catch fire at low oven temperatures, but the heat will still damage the material. You won’t be able to use the wooden cookware like you used to.

The wood may have warped, the glued parts may have been damaged, and the surface may no longer be as smooth as it once was. Don’t take the chance. Even if the wood is thick, it will be damaged if exposed to heat for an extended period.


Some plastics are heat resistant. But how do you know if the plastic dish will withstand the heat of your oven? So far, no plastic dish manufacturer has claimed to have produced oven-safe plastic dishes. To be safe, avoid putting anything plastic inside your oven.

Is the Pizza Box Recyclable?

Thinking that the pizza box is composed of cardboard and hence readily recyclable; nevertheless, this is not always the case. The contamination of your pizza box determines whether or not it gets in the recycling bin.

Recycling cardboard or any other paper product is first shredded and then combined with different chemicals such as surfactants and sodium silicate. The chemicals convert the shredded paper into pulp, which is subsequently subjected to an ink removal technique and filtered to remove tapes and staples. Tapes and staples are a form of pollutant. However, they are easily removed. 

However, if the paper contains grease, it will be combined with the pulp, lowering the quality or altogether destroying the batch. This is one of the reasons why you should inspect your pizza box before tossing it in the recycle bin. Furthermore, tainted pizza boxes, as well as those carrying burgers or cakes, are almost unrecyclable.

As a result, before putting out your pizza box, ensure it is devoid of any leftovers and does not include any cheese, tissues, or wrappers. The box must be empty. If your box came with an extra layer of waxed paper below and the oil is on that rather than the box, simply remove the paper and recycle the box.

If the bottom of the box has been destroyed by oil and grease, you can rip out the lid and other non-contaminated parts and pieces to submit for recycling. If the entire box is destroyed, the best option is to shred it and compost it.

Why are there holes in pizza boxes?

The perforations allow the steam that accumulates while the pizza is heated to escape. It keeps the pizza from becoming mushy.

What are the dimensions and thickness of a pizza box?

The thickness of corrugated pizza boxes ranges between 1/32′′ and 3/16′′. A personal pizza box is 8 inches square, a small pizza box is 10 inches square, a medium pizza box is 12 inches square, a large pizza box is 14 inches square, and an extra large pizza box is 16 inches square.

What is the significance of the square shape of pizza boxes?

Pizza boxes are square because they are less expensive to manufacture and can be readily built from a single sheet of cardboard.

Conclusion – Can Cardboard Be Used in The Oven?

To summarize, can you put cardboard in the oven? Cardboard does not catch fire until it is heated to temperatures above 400°F. Even if you could keep the oven temperature below 400°F, putting cardboard in the oven while it is on is not safe.

If the cardboard comes into contact with the burner, it may catch fire. Furthermore, if the cardboard contains flammable chemicals, it can catch fire even at low temperatures. To avoid starting a fire, avoid putting cardboard in the oven.


Editorial Staff

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