Urns come in all shapes and sizes. There are a couple of simple ways to make a calculation of the urn size you need to buy, which is measured in cubic inches. The industry standard, set by the Cremation Association of North America, is 200 cubic inches for the average adult. Although the estimations are not always exact, a calculation based on weight and height should give you a very close approximation of the volume of ashes you can expect.
Converting Weight to Cubic Inches
A quick way to make an estimate is to take the body weight in pounds and convert it to cubic inches at a 1:1 ratio. This conversion merely indicates a minimum, so you can always select an urn with a larger capacity if you prefer. For example, a person who weighed 150 pounds may require an urn that holds at least 200 cubic inches. When converting from kilograms, multiply the weight by 2.2 to get weight in pounds. If you want to use a container that has a volumetric capacity, you would divide the number of cubic inches by 14.44 to get the amount of cups. As such, 150 cubic inches is nearly 10.5 cups of ashes. However, this weight conversion is a general rule that is not always precise. People who weigh a great deal more than average may not necessarily need a far larger urn.
Considering Height in the Calculation
When selecting urns for people who were of above-average size, you should consider height in the equation. During the cremation process, most of the body’s fat is burned away. Bones are primarily what are left in cremated remains. For example, a person who weighed 300 pounds probably does not need an urn that holds 300 cubic inches. However, the ashes of a person who was unusually tall may require a bigger urn, as bones make up most of the ashes. So, as a general guideline, you should consider getting a larger urn for anyone who is over 6 feet tall.
Most urns are designed to hold the ashes of just one person, unless otherwise specified. If you wish to put the ashes of more than one person into an urn, such as a married couple, you should look at companion urns that are intended to hold at least two full sets of ashes. Otherwise, using these calculations based on weight and height will give you the best approximation of the cremation urn size you need.