Can You Put A Cold Glassware In The Oven? (Are They Oven Safe?)

The glass dish can be used to store leftovers, for preparing your meals in other ways or to freeze them if you want. However, glass dishes can break for a variety of reasons.

You will find in this article everything you need to know about what to do and what not to do while using glassware in the oven, especially when it is cold.

Is it okay to use a glass dish in an oven?


No, it is not recommended that you use glass dishes in an oven as they might break as a result of the heat. Glass is one of the most fragile objects in the world. Glass usually breaks when heated in an oven, especially when it’s a low-quality glass dish.

If you don’t have another option, check the glassware to make sure it’s oven-safe. Generally, if the glassware is oven-safe, then there is a possibility that it will not break in the oven.

Will a cold glassware break when kept in an oven??

glass break in oven

When a casserole or a glass dish is immediately transferred from a cold temperature to a high temperature, It’ll break due to the drastic temperature change. Usually, when this happens, the glass will expand and shatter. An immediate temperature change can create pressure within the dish. This is known as a thermal shock!

Make sure that your glassware is not with metal lining or colored glass as they tend to break more often when it’s heated up before bringing the temperature down to room temperature.


What causes the glass dishes to break?

Glassware can break for a variety of reasons, including the type of dish and the temperature. Here are some of the most significant reasons why glass dishes break.


Thermal shock

As mentioned previously, thermal shock is the most important reason not to use cold glassware in an oven. Thermal shock occurs due to the rapid change of temperatures. The casserole cannot handle the high temperature and will shatter eventually. The maximum number of breakage of glassware or casserole happens due to thermal shock.

For example, keeping frozen glassware in the oven the minute after taking it out of the refrigerator will create thermal shock and lead to breakage of the glassware.


When the dishes are scratched

When the dishes are worn and torn, many scratches can be on them. Those scratches will expand, crack and break. When the glass expands due to the high temperature, it cannot withstand such a change as used a lot before.

When the glassware is put inside the oven, it will expand due to the high temperature, now, the scratches on the glassware will be cracked due to the expansion, and the glassware will eventually shatter or break.


High temperatures

high temperature

If you keep cold or even room temperature glassware inside the oven, there’s a huge possibility of shattering or breaking because of the high temperature.

It always depends on the brand, and the quality of the casserole used because few brands can sustain high temperatures while some low-quality brands cannot. So choosing a well-trusted brand such as pyrex, Luminarc, Libbey, etc.


Preventive measures to avoid breakage

There are a few preventive measures you can take a look at before using any glassware in an oven.


Defrost the casserole

Even the famous and good quality glassware will break and shatter in case of the rapid temperature change. Defrost the glassware before using it in the oven so that it won’t shatter due to the sudden temperature change.

Famous glassware brand pyrex has even given out instructions and preventive measures that might help you.


Look out for scratches.

Scratches can develop into a void due to high temperature and shatter with pressure. We definitely would not mind scratches as such a big issue, but they can be one of the essential reasons why glassware breaks.  Do not use glassware that has scratches on them.

Cook with liquids

Cover the bottom of the glassware or casserole with liquid before cooking vegetables or meat. When there is no liquid, the food will cook unevenly, the glass will expand, and the pressure will be on the glass, eventually leading to breakage.

Leave space for the food to expand.

oven dish

While cooking or baking in glassware, don’t forget to leave some space for the food items to expand. Usually, meat, chicken, or bakery items will be expanded during the cooking process, but when there is no space, the glassware will expand along with the food and eventually break. Cooking the food with liquid is also an essential measure.



At what temperature does the casserole or glassware break?

The glassware breaks at 450° celsius. This cannot be the accurate temperature as the glassware and the oven differs in the brand. To be on the safer side, we can fix the temperature from 400 – 450 degrees celsius.

Disclaimer: This information is only for oven-safe glassware.


How to check whether the glassware is safe for the oven?

It’ll be mentioned as “oven-safe” on the package of the glassware. Or sometimes it’ll be mentioned on the glassware itself.



It is not advisable to put cold glass dishes in an oven, as the rapid change of temperatures can create pressure and break the glassware or casserole. Oven-safe glassware can be used in the oven but only when at room temperature. Keep in mind the causes and the preventive measures before using glassware in an oven.

Leave a Comment