The one cubic inch per pound rule
Funeral homes and urn makers size urns with a simple rule of thumb: about 1 cubic inch of capacity for every pound of healthy body weight. Cremated remains are mostly bone, so a person's frame matters more than their weight. Use a typical adult weight rather than a weight after a long illness or a period of heavy weight, and round up when in doubt. The same rule is commonly used for pets.
Choosing the right urn
- Where it will go. A niche, an in-ground cremation plot, a shelf at home and scattering each suit different urns. Cemeteries may require an urn vault for burial.
- Material. Metal, wood, stone and ceramic suit display and niches; biodegradable urns of paper, salt or plant fiber are meant for water or green burial.
- Where to buy. Under the FTC Funeral Rule, a funeral home must accept an urn you bought elsewhere, without a handling fee.
For more, read How to Choose an Urn, What Is a Columbarium? and Where Can You Scatter Ashes?, or find cemeteries with columbariums.
Updated November 8, 2026 · Built and reviewed by the Cemetery Directory USA editors.This tool runs in your browser; nothing you enter is sent to us or stored.