What Do The Numbers On Your Pyrex Dishware Actually Mean?

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Pyrex is an iconic kitchenware brand that's been available for customers to purchase since 1915, when the Corning Glass Works Company released their first line of ovenware under the name. Since then, it has become a household staple, with any number of retired Pyrex patterns that collectors would want to see back on store shelves. Over the years, the company has released a wide range of cookware in different dish styles, colors, and patterns. With that range of products comes markings to help customers identify what they have in their collection and what they come across on the secondhand market. If you've ever looked at the bottom of your Pyrex and been confused by the numbers that you see, this should help.

Typically, you will see two different numbers on the bottom of Pyrex dishes, with both numbers found directly above the word trademark. One of those numbers is for the size of the dish, while the other is the model number. For lids, you'll often find these marks on either the rim or under the handles. The sizing is quite easy to determine, as it will usually have the abbreviations for the measurements, such as qt for quart and pt for pint. However, the real number you want to pay attention to is the model number. This is the number that will help you figure out both the exact shape and size of the cookware itself and any lids that are associated with those pieces, as the lids will also have the same number as their corresponding dish. The backstamp can be a sign of value on vintage Pyrex, and that includes the dish style number.

When you go hunting at your local thrift store, you might come across some rare Pyrex, and checking the serial number can give you a better idea of what style of dish you've found. It's important to know that the style number will not correspond to a specific pattern or color, but it'll let you know if the pattern or color is supposed to be found on a specific dish, as certain designs and colors were not released on specific dishware styles.

For the mixing bowls, which are a popular release across a variety of colors and patterns, there are two different types you might find in four sizes. The regular bowls are numbered 401 through 404, while the second set of mixing bowls are the Cinderella style, with the specialty pour handles, numbered 441 through 444.

Casserole dishes, such as the Bake, Serve, and Store, are numbered 471 through 473. There's also oval casserole dishes in two sizes, often released as promotional pieces, and those can be numbered 043 and 045 or 943 and 945. Similar oval divided casserole dishes can be found with their own numbers, 963 and 053.

Beyond these common pieces, you can also find Refrigerator Sets with the numbers 501 through 503, Utility Dishes numbered 231 and 232, Pie Pans with a Rim have numbers between 205 to 211, a square Baking Dish with the number 922, then a Rectangular Pan numbered 933, and a Loaf Pan with the number 913. Finally, butter dishes are another Pyrex piece to look out for with the number 72 on them.