It's one of the first questions people ask, and one of the easiest to answer once you know the rule. Urn sizing sounds complicated. It really isn't.
Here's everything you need to know to choose the right size — and why when in doubt, you should always go bigger.
The rule is simple
One pound of body weight before cremation equals one cubic inch of urn capacity. That's it.
So if your loved one weighed 160 lbs, you need an urn with at least 160 cubic inches of capacity. If they weighed 200 lbs, you need at least 200 cubic inches. Round up to the nearest size, not down.
This rule applies to traditional flame cremation. If your loved one was aquamated (water cremation), the process typically produces more ash — sizing up is especially important in that case, or message us and we'll help you figure out the right fit.
All six Fauna urn sizes — the same design, same setting, same colour. The difference in scale is significant.
The Fauna size guide
We label our urns by the maximum body weight they can accommodate before flame cremation. Here's a quick reference:
| Urn size | Body weight before flame cremation | Volume |
|---|---|---|
| 25 lb | Up to 25 lbs | 25 in³ |
| 50 lb | Up to 50 lbs | 50 in³ |
| 100 lb | Up to 100 lbs | 100 in³ |
| 150 lb | Up to 150 lbs | 150 in³ |
| 200 lb | Up to 200 lbs | 200 in³ |
| 250 lb | Up to 250 lbs | 250 in³ |
Always size up. An urn with a little extra room is always the right call — there's no downside to choosing one size larger.
Size depends on your plan, not just the weight
Keeping all of the ashes in one place? Match the urn size to body weight and round up if you're close to the capacity limit. The 200 lb urn is the right fit for most adults.
Splitting ashes between family members? The combined capacity of all your urns just needs to equal or exceed the total body weight before cremation.
Scattering most of the ashes and keeping a small amount? A smaller urn is usually enough for a meaningful keepsake portion.
Columbarium placement? Capacity matters but so do exterior dimensions — niches vary in size between facilities. Check the niche dimensions with the cemetery before buying.
The bottom line
The rule works and it's easy to apply. Start with body weight, match it to the nearest size, and round up if you're close to the limit. That's really all there is to it.
If you're not sure of the exact weight, or you're dividing ashes between family members and not sure how to think about the split — we're here. Message us and we'll help you work through it.
Visit our Sizing Guide for a step-by-step walkthrough, or email us directly — we'll help you choose.
Fauna urns are modern cremation urns designed and made to order in Vancouver, Canada. Available in six sizes and eight colours, with free shipping and free returns.
Browse all urns