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Is it safe to microwave a pizza box?

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Do you need to use a plate, or can you microwave a pizza box? When you’re feeling too lazy to cook, we either order delivery or grab and quick takeout meal. If your pizza arrives cold, or there was a traffic-jam on the way home, are you able to through it in the microwave as it is?

Pizza boxes are generally made of cardboard, which is generally considered to be microwave safe. However, there are a few rules of thumb to remember when you microwave cardboard.

Pizza is one the most popularly ordered items because it is cheap, plentiful and convenient because some pizzerias are even open 24/7. As a result, microwaving a pizza box isn’t as farfetched as it may seem at first.

Is a cardboard pizza box heat-resistant?

When discussing cookware, its important to first distinguish the difference between the terms heat-resistant and fire-resistant.

  • Heat-resistant withstands temperatures up to 140°C
  • Fire-resistant withstands heating between 250-300°C.

Cardboard or corrugated board is a combustible material that should be kept away from sparks or open flame. Furthermore, cardboard has an ignition temperature of 427°C in which it will spontaneously combust.

So when staring at the pizza box with a few leftover slices inside, it’s possible to question what happens when you put a pizza box in the microwave to prevent burning the house down.

Cardboard pizza boxes are solely intended for delivery, and are devised with that specific intention. Several important considerations are made when manufacturing the box.

A cardboard pizza box are designed to be:

  • Durable for stacking
  • Heat-resistant up to 80°C
  • Retain warmth
  • Prevent soggy pizza crust

Occasionally we feel invincible and like the masters of our domain. However, when it comes to specific materials they have certain functions and respond based on scientific principles.

In this case, you now learned that a pizza box is primarily heat-resistant and designed with that specific intention. If you have experimented with your home microwave and found that a few slices can be heated up in a pizza box, then you can quickly warm up the leftover treat.

Are all cardboard pizza boxes microwavable?

people sitting crossed legged on the floor with five pizzas in pizza boxes.

Even though high quality pizza boxes are designed with heat-resistant functionality, that doesn’t necessary mean all cardboard pizza boxes are safe to use in the microwave.

The primary concern is that some pizza boxes have additional functionality built into the container. A thin aluminum foil coating on the inside, metal clasps on the outside or plastic pieces may adorn the box, which are just not safe to use in the microwave.

Closely read the manufacturer recommendations on the side of the pizza box. Some boxes have been intentionally designed to withstand the microwave.

An alternative option is to place the leftover pizza on a microwave safe plate and heat up as normal. Realize that this method results in chewy pizza that is no longer crunchy.

Want to know how to reheat pizza in the microwave? These simple microwave instructions are the best way to take your delicacy to the next level with no more concerns about soggy crust!

Things to know before microwaving a pizza box

Microwaving a pizza box is an easy way to reheat leftover pizza and avoid dirtying a dish in the process. However, there are few things you need to be aware when choosing this method.

  • Never place an empty pizza box in the microwave without the pizza. Pizza boxes are flammable and can combust when heated with high temperatures without pizza to absorb the microwave’s energy.
  • Double-check to make sure that the pizza box does not contain any metal parts. It’s never safe to microwave metal pieces because they may spark and damage your appliance.
  • Look at the materials that the pizza box is made out of because some boxes are contain plastic or wax coating. If it feels smooth or slick to the touch, it could partially melt and may not be safe to microwave.

The best recommendation is to avoid using a pizza box to reheat leftovers. I understand the desire to eliminate a dirty dish, however the risk is not worth the reward.

Stick to more conventional methods like using a plate with a paper towel to help absorb moisture and prevent an overly soggy crust. Furthermore, consider using a microwave crisper pan or the toaster oven because the pizza will retain the crispy crust and the cheese will melt more evenly.

Can you microwave pizza box?