Choose the Right Size
Urn sizing comes down to one number: cubic inches. It sounds clinical, but it's the one measurement that actually tells you whether an urn will hold what it needs to.
The general rule
Cremated remains work out to roughly 1 cubic inch of space for every pound of the person's body weight before passing. A urn for someone who weighed around 150 lbs should hold at least 150 cubic inches. Most standard adult urns are built to 180–200 cubic inches, which comfortably covers the majority of adults.
This is an estimate, not an exact science. Bone density, the crematory's process, and individual variation all shift the number slightly. When in doubt, size up rather than down. An urn that's a little roomier is a non-issue. One that's too small is a real problem after the fact.
Quick reference
- Under 100 lbs: 100–150 cubic inches
- 100–200 lbs: 180–220 cubic inches
- Over 200 lbs: 250+ cubic inches, or consider an oversized urn
If you're not sure of the weight
That's normal, and it's not something families usually have on hand. If you already have the remains, the funeral home or crematory can tell you the exact weight, since cremated remains are typically weighed and provided in a temporary container beforehand. If you're purchasing ahead of that step, choosing a standard 200 cubic inch urn is a safe, common default for an average-sized adult.
Other sizing situations
Keepsake urns are intentionally small (usually 3–20 cubic inches) and hold only a symbolic portion of remains, meant for sharing among family members or keeping close rather than housing the full amount.
Companion urns are built to hold two individuals' remains together, and need roughly double the standard capacity. See our companion urn guide for more on how that works in practice.
Infant and child urns don't scale reliably from the standard adult formula, since the ratio of cubic inches to weight isn't linear at such small volumes. Most infant urns fall in the 3–20 cubic inch range, closer to keepsake sizing than a scaled-down adult urn. The funeral home handling arrangements can typically confirm the exact volume needed, and we'd always recommend checking with them directly rather than estimating for this particular size range.
A note on capacity vs. displayed size
Two urns can look like similar sizes on a shelf and still hold very different volumes, because base thickness, lid design, and interior shape all affect usable space. Every product page on this site lists its cubic inch capacity directly, so you're never guessing from a photo alone.
If you're still unsure which size is right for your situation, our team is easy to reach and happy to walk through it with you.