Last Updated: July 15, 2021

The original Corningware Pyroceram cookware is safe to put in the oven at temperatures exceeding 500 F.

The stoneware version of Corningware is also safe to put inside the torrid perimeters of the oven but at temperatures typically lower than the one mentioned above, often less than 350 F.

CorningWare Pyroceram cookware is well built to withstand sudden temperature changes such as the heat gradient observed between a preheated oven and a freezer.

And because of this, the product can be taken out from the fridge and placed directly inside the oven without suffering any thermal shock.

It can also be used directly on a stovetop or go directly under or above the broiling and grilling element in the oven respectively.

As for the stoneware version, it’s not as resilient to thermal shock as the original version because of its constituent material, and you’re better off cooling the frozen dish first before putting it inside the oven.

It’s also not safe to expose directly under a broiler or over a grilling element, and should also not be used directly on a stovetop as it can crack or break.

CorningWare is built for the heat

Corningware Pyroceram (meaning Corningware products that use Pyroceram as the base material) is actually built for the heat.

The Pyroceram, which is a synthetic glass-ceramic that was accidentally discovered in an experiment centered on photosensitive glass in the 19th century, is what gives this stability and sturdiness.

The material can withstand thermal shock; sudden temperature change of up to 840 F, unlike stoneware and glass which will instantly or eventually shatter when subjected to this intense type of temperature change.

Aside that, Pyroceram also has a very high resistance to heat which makes it suitable for high heat cooking.

In fact, in the official product website of the CorningWare brand, no reference is actually made with respect to the maximum cooking temperature the Pyroceram cookware can be subjected to — pointing to the stability of the material for all temperatures a household oven will ever be subjected to.

This high heat resistance is also why Pyroceram can be used directly on a stovetop without cracking or breaking.

As a fascinating addition, Pyroceram is actually the material used on missile nose cones to manage rapid temperature fluctuations during space travel. Such a really marvelous invention isn’t it?

The stoneware and porcelain versions

The Pyroceram version of Corningware cookware enjoyed a long spell of business until the late 1990’s when the company transitioned to ceramic stoneware for marketing reasons.

The newer material wasn’t as sturdy and heat durable as the original Pyroceram but it allowed for a wide variety of colors and designs that was appealing to customers. The retired Pyroceram product was later reintroduced in 2009 due to consumer demand.

Stoneware Coringware products and those made out of other materials other than Pyroceram (such as porcelain) aren’t shock resistant.

They are prone to shattering the moment you place them frozen inside a preheated oven. They also do not farewell on the stovetop which is why they’re slapped with the “not for stovetop” label on their bottom.

Despite their fragility when it comes to heat application, stoneware and porcelain products are actually safe to put inside the oven, but often at temperatures lower than 350 F.

Are Corningware lids oven safe?

Corningware lids aren’t safe to put under direct heat (broiling or grilling) because they’re made out of tempered borosilicate or soda-lime glass which have lower tolerance to heat.

They also have a lower tolerance for thermal shock unlike the body casserole. So avoid putting them in the oven while reheating dishes inside the Corningware cookware.

Can you put Corningware in toaster oven?

For the Pyroceram version, it’s completely safe to use in a toaster oven because of its high heat resistance.

For the stoneware or porcelain version — check the manual to find out if that is what you have, and avoid putting it in the toaster oven because of the heating element. If I’m correct, that’s what Corningware’s manual officially recommends.

Here’s how to ensure the integrity of your stoneware or porcelain Corningware product.

  1. Avoid the broiler and the griller like the plague.
  2. Avoid the microwave browning element too.
  3. Avoid direct heat source i.e. oven heat vent, pilot lights and open flames.
  4. Avoid shocking the product thermally by allowing it to come to room temperature first before putting it in an oven preheated to no more than 400F, ditching the practice of adding cold liquid to a hot product and vice versa, ditching the practice of placing hot product on a wet surface, or handling a hot product with a wet or cold cloth. To handle hot items, use a dry towel or potholder.

Can you put Corningware in a microwave oven?

Both the Pyroceram version and the stoneware or porcelain versions are safe to put in the microwave under strict observation of the following protocols, especially for the latter.

  1. Ensure that no metal parts are attached to the cookware you plan on using in the microwave. There are also products with metallic designs on them such as the gold leaf, silver leaf, or platinum leaf on them. These are not recommended to be put inside the microwave as they may cause arcing (sparking).
  2. Ensure that the cookware is in perfect condition without any obvious cracks and pores.
  3. Do not microwave popcorn in it.
  4. Do not microwave centura which is another type of dish made by CorningWare.
  5. Do not use it to hold popcorn bags or other microwave convenience food.
  6. Do not heat it empty in the microwave.
  7. Do not heat small amount of food in it.
  8. Do not over heat oil based food in it. They can get extremely hot and cause the base plate, cup or bowl to shatter.

What about Corningware products marketed under the Corelle brand?

These are mostly the stoneware and porcelain cookware we’re talking about, although the Pyroceram version under this brand still marketed as Corningware Pyroceram also exists in the Asia-Pacific region.

They are safe to use in the oven but at temperatures below 350 F. All other rules outlined in the toaster oven section applies to them too.

What about Corelle products?

The Corelle brand, as one of the many brands under Corning Inc., offers dishware that are break resistant and may have matching designs to many CorningWare patterns.

They include bowls, plates, mugs and cups. However, most of the products are made with either porcelain or glazed stoneware with the exception of the very few products made with Pyroceram. Check the manual to find out which, but if you’re outside of Asia Pacific it’s even going to be very difficult to find such variance.

Because of these base materials, they are not recommended to be used on a stovetop, they are not direct heat resistant, and are only safe to put in a pre-heated oven at temperatures below 350 F.

They also have poor tolerance to thermal shock and thus should never be introduced to rapid heat change situations as outlined in the toaster oven section.

Corelle products are typically microwave safe.

What about products in the Vision brand?

The vision brand is one of the brands of Corning inc. that specializes in cookware made of a pioneering see-through Pyroceram.

Because of this, it also has thermal properties like that of Corningware Pyroceram cookware, and thus can be used just like it, meaning that it can be subject to situations of rapid temperature fluctuation and subject to household grilling and broiling elements without any problem.

Final thoughts

Corningware made out of Pyroceram is perfectly safe to put in the oven at any cooking temperature, but the other variant which is made using porcelain or stoneware is usually only resistant to about 350 F.

Additionally, Pyroceram Coringware can be used directly from the freezer without any thermal shock suffered, and it can also be used in the toaster oven for baking purposes.

Stoneware and porcelain Conringwares typically aren’t safe to transfer directly from the freezer to oven, and use in toaster oven.