If you are a fan of pizza either delivery or store-bought, you’ve probably wondered, can you put cardboard in the oven? Delivery pizza comes in a cardboard box, while frozen store-bought pizza is packaged with cardboard. Does that cardboard help the pizza become crisp? Is it safe to put cardboard in the oven? In short, cardboard should not be used in the oven. In this post, I’ll explain why it’s not safe to put cardboard in the oven, and the best way to reheat pizza without cardboard.

We all love pizza! My family is a big fan! Sometimes it’s easier to get delivery, and other times we may get a store-bought frozen pizza, and when I’m feeling really motivated I’ll make a homemade pizza. No matter what, we always have leftovers. This means that the next day, we have an easy lunch. All we need to do is reheat the pizza!
Whether you get delivery or store-bought, pizza comes with cardboard. Maybe you accidentally put the cardboard circle in the oven when you slipped your frozen pizza in to bake, but is it safe? Should you use that cardboard to bake your pizza? What about delivery? Should you reheat your pizza in the pizza box? While many people have used cardboard without a problem, there are others who have not. You should never put cardboard in the oven. Here’s why!
Can You Put Cardboard in the Oven?
You should never put cardboard in the oven! Cardboard is a combustible material. This means that it will ignite or catch fire under a particular temperature. The ignition point of cardboard is 427 F. This means, technically if the cardboard isn’t heated to the point of 427 F it won’t catch fire. The risk of ignition increases depending on the type of oven you have. Older ovens increase your risk of ignition because their heating elements are more exposed to the inside of the oven. The heating element in newer ovens is better covered which decreases the risk of ignition. But no matter whether you have an older or newer oven, you should never take the risk of putting cardboard in the oven!
Many people claim to have had success using cardboard in the oven. This is likely because they have not heated the cardboard to 427 F or higher. However, just because you may not have your oven set to that temperature, does not mean you don’t run the risk of starting a fire.
While placing cardboard in the oven with the pizza on top is less of a risk since the cardboard is not in direct contact with the heating source, the risk is still there. There is absolutely no reason to take the risk of placing cardboard in your oven when there are so many better alternatives that will not cause your kitchen to go up in smoke!
Why Is Frozen Pizza Packaged with Cardboard?
Since it is unsafe to put cardboard in the oven, why do manufacturers package frozen pizza with cardboard?
The reason manufacturers use cardboard with frozen pizza is to provide support for the pizza base. Without something on the bottom of the pizza to hold it all together, the pizza would bend and shift, during the shipping process from the manufacturer to the store, and then the store to your home. A simple piece of cardboard is a cost-effective solution to ensure the frozen pizza arrives at your home in one piece.
You will notice when you read the directions on how to prepare the frozen pizza it will always tell you to remove the cardboard and not put the pizza in the oven with the cardboard still on the bottom.
Why You Should Never Use Cardboard in the Oven
There are three main reasons you should never use cardboard in the oven.
- Oven Fire: The threat of causing spontaneous combustion in your oven should be reason enough to never use cardboard in the oven. Not only can this ruin your oven, but it can also cause your kitchen to go up in smoke, and even cause a house fire.
- Slow Cooking Time: Leaving that cardboard round on the bottom of your pizza can actually slow down cooking time. Making it take longer to get to that delicious pizza you’re hungry to eat. That extra layer between the heat source and your pizza means it will take more time for the crust to cook and become crisp.
- Releases Toxic Chemicals: The cardboard underneath your pizza is likely treated with an anti-grease layer. When these chemicals are heated the fumes are released and absorbed into your pizza causing your food to not only taste strange but also cause you to ingest potentially harmful ingredients.
How to Cook or Reheat Frozen Pizza Without Cardboard
While frozen store-bought comes with cardboard, and pizza is delivered in cardboard, there is no reason you need to use it during the cooking or reheating process. Before you decide which method to use to bake your frozen pizza, read the directions. The directions will likely tell you which method is best to achieve a crisp crust.
Directly On the Rack
One of the most common ways to bake a pizza is to place it directly on the middle rack. I know the first time I did this I worried that melted cheese would drop to the bottom of my oven, but luckily that has never happened. Always place your pizza on the middle rack to achieve an even bake all around. If you place the pizza too low in the oven, you run the risk of burning the bottom. If you place the pizza too high, you run the risk of burning the cheese. The middle oven rack is the sweet spot!
Pizza Stone
A pizza stone is another great option! Ceramic pizza stones are made specifically for pizza. You can place your pizza on top without worrying about dripping cheese or toppings in your oven, and yet still get a super crispy crust. You can then take the stone right out of the oven and cut your pizza into slices.
Baking Sheet
Using a cooke sheet or baking sheet is another way to go if you don’t have a pizza stone. Place your pizza on top of the cookie sheet and cook according to the package directions. There’s no need to line it with parchment paper or aluminum foil. The pizza will bake and crisp nicely without sticking to the baking sheet.
Pizza Pan
Similar to a baking sheet, a pizza pan is the same thing only it’s round instead of rectangular. These are ideal for fitting your pizza. A rectangular baking pan may not be the right size to fit your pizza evenly, but a pizza pan with be a nice tight fit!
Aluminum Foil
You can also wrap the bottom of the pizza with aluminum foil, or wrap the aluminum foil around the rack of your oven. Aluminum foil is safe to use in the oven. Just be sure to wrap the rack with foil before you preheat the oven to avoid burning yourself!
Baking Dish
A casserole dish or baking dish is also oven safe. Most baking dishes are ceramic or glass which means it will take longer for the pizza to bake, but if you don’t have any of the above, this is a safe route to take.
How Do You Reheat Pizza Without Cardboard
Above I described the ways to bake a frozen store-bought pizza without using the packaged cardboard. But what about delivery pizza? Delivery pizza arrives in a cardboard pizza box. You should never place the cardboard pizza box in the oven. But here are some easy ways to reheat your delivery pizza after it’s gone cold.
In the Oven
Preheat your oven, and place it on any of the above-mentioned kitchen tools. You may use a baking sheet, pizza stone, pizza pan, or aluminum foil. I don’t recommend putting pizza slices directly on the oven rack as they are too small and thin and could easily slip between the rack and fall to the bottom of the oven. Using an oven will give you a crisp crust and a melty cheesy top.
In the Toaster Oven
Instead of waiting for your larger oven to preheat, the toaster oven is a faster solution. It will reheat your pizza in half the time because it is much smaller and doesn’t require 15-30 minutes to heat to your desired temperature. Instead, you can place your pizza slices directly on the toaster oven tray to warm back up. You’ll still get a super crispy crust.
In the Microwave
I have to admit this is the way I reheat my pizza the most often. Not because it’s the best, but because it’s by far the easiest. Simply place your slices of pizza on a microwave-safe plate and heat for less than a minute. Your pizza will warm up nicely, but you won’t have a crisp crust.
On the Grill
If it’s summer and you have the grill fired up, this is a tasty option to reheat your pizza. Be sure to place your pizza slices on aluminum foil to avoid the pizza dough from burning against the open flame.
On the Stovetop
Not the most common way to reheat pizza, but definitely a possibility, you can heat a large pan over medium-high heat, and place your slices of pizza inside. The crust will become crisp but it may take more time for the cheese to become warm and melty.
FAQS
No, do not ever put a pizza box in the oven. If the cardboard reaches a temperature of 427 degrees fahrenheit the cardboard will ignite. Even if you don’t turn your oven up to the temperature there is still a chance that the cardboard will catch fire, especially if you have an older model oven. To avoid fire, never put any type of cardboard in the oven.
No, it is not okay to cook pizza on cardboard. If your frozen pizza comes on a round shaped piece of cardboard, make sure to discard it before cooking your pizza.
Cardboard will catch fire at 427 degrees Fahrenheit.
Final Thoughts
It is never safe to put cardboard in the oven. Although some people may have purposefully or accidentally placed cardboard in the oven without it catching fire, it is never advised to do so. While cardboard combusts at a temperature of 427 F, it can easily catch fire if you have an older model oven in which the heating element is exposed to the oven. Even if you have a newer model oven, it is not worth the risk. There are so many other ways to heat or reheat items whether they be pizza or other types of foods, that there is never a need for cardboard to ever be put in the oven.
More Helpful Cooking Tips
- Can you put glass in the oven?
- Can you put aluminum foil in the air fryer?
- Can you freeze scones?
- Can you froth almond milk?
Please comment below if you found this article helpful or have any additional questions. You can also follow me on Instagram, Pinterest, and Facebook for more family-friendly vegan recipes!
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