Urn size calculator
Estimate the urn capacity you need using the common funeral-industry rule of thumb: about one cubic inch of capacity per pound of healthy body weight.
This is an estimate, not a guarantee of fit. The volume of cremated remains varies with height, bone density and other factors. Confirm the actual volume with the crematory or funeral home, and confirm capacity with the urn seller before buying — especially for a niche with fixed dimensions.
Understanding urn sizes
| Urn type | Typical capacity | Use |
|---|---|---|
| Keepsake | About 1–10 cubic inches | A small portion, often one of several for family members |
| Small / shared | About 20–100 cubic inches | A larger portion when remains are divided |
| Standard adult | About 180–220 cubic inches | The remains of most adults |
| Large / extra-large | About 250 cubic inches or more | Taller or larger adults |
| Companion | About 300–450 cubic inches | Two people, in one shared space or two compartments |
Capacity vs. external dimensions
An urn's capacity (inside volume, in cubic inches) is what determines whether remains will fit. Its external dimensions matter for where it will go — a niche, a shelf, or an urn vault for burial. Walls, lids and decorative bases mean two urns with the same outside size can hold very different amounts. Always check both.
Companion urns
Companion urns hold the remains of two people, either mixed in one space or in separate compartments. When the first person dies, the second person's remains will be added later, so confirm how the urn is sealed and reopened, and whether a cemetery or niche can accommodate it.
Biodegradable urns
Biodegradable urns for water or earth burial list capacity the same way. Some tree or planter urns are designed for only a portion of remains or include a soil mix — check the product details. See biodegradable urns.