Hello, I'm a subject matter expert with a background in home canning and preserving. When it comes to canning jars, the size you're referring to is a standard measurement in the United States, which is different from the metric system used in many other countries.

A quart canning jar typically holds about 32 ounces or roughly 946 milliliters. The dimensions of a quart jar can vary slightly depending on the brand and style, but generally, it stands about 7 to 8 inches tall and has a diameter of about 3.25 to 3.5 inches at the top. The actual volume of the jar might be slightly more than a quart to allow for headspace, which is the space between the top of the food and the lid. This is an important factor in the canning process to prevent overpressure and ensure a safe seal.

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Wide-mouth Kerr quart jars are 3.9 inches in diameter and 6.6 inches tall. A case of 12 has a dry weight of 14 lbs. Standard mouth Ball quart jars have a 3.5-inch diameter and a 6.9-inch height.read more >>