The right size urn for an exotic pet, from thimble to large
By the usual sizing rule, cats and dogs need roughly 12 cu in (cat); 70 cu in (dog)[1] of urn space. Most small exotics need a fraction of that. Enter your pet's weight to find a container that actually fits.
- Volume in cubic inches and millilitres
- Keepsake and sharing options included
- Avoid buying an urn that's ten times too big
Urn size calculator
Enter your pet's healthy adult weight. We size the urn using the industry rule of 1 cubic inch per pound, plus 10% room to spare.
Recommended urn size
5.5 cu in (90 mL)
Look for: Small (up to 20 cu in)
| Total ashes (by volume) | 5 cu in (82 mL) |
|---|---|
| Expected ash weight | 2.4 oz–4 oz |
| Urn with 10% margin | 5.5 cu in (90 mL) |
Standard sizes: small up to 20, medium up to 60, large up to 120 and extra large 200+ cubic inches. If you're between sizes, choose the larger one.
Source: Embrace Pet Insurance - Bury or Cremate Your Dog? Costs, Pros & Cons; Our estimate. 1 cu in per lb is an industry rule of thumb
Next step: Find urns and prices near you →
Getting started
How to use the urn calculator for a small or large exotic
Enter your pet's weight. For small exotics, switch to kilograms and use decimals, so a 140 g glider is 0.14 kg. Then choose how many people will share the ashes, and whether each person would like a keepsake urn of about 3 cubic inches as well as a main container.
The calculator shows the volume you need in cubic inches and millilitres, suggests a standard urn size band, estimates the ash weight and shows how much goes into keepsake urns. It updates as you change anything, so you can try a few combinations before deciding.
How it calculates
The one-cubic-inch-per-pound rule, and the margin we add
Urn makers size containers using a simple rule: one cubic inch of space for every pound of body weight. The calculator adds 10% as a margin, because ashes don't settle perfectly and you'll want room for a lid and any bag the provider uses. Cremated remains weigh about 3-5% of body weight[2], and the volume rule is designed to hold that comfortably.
Standard sizes fall into rough bands: small urns around 20 cubic inches, medium around 60, large around 120 and extra-large 200 or more. Keepsake urns are usually about 3 cubic inches, and pendants hold around 0.05 cubic inches, about a pinch.
The rule is a volume shortcut for the weight of ashes, which a forensic study of 100 cremations put at about 3.5% of adult body weight. For a ferret, which the Merck Veterinary Manual puts at around 1.2 to 2 kg, the rule gives roughly 3 to 4.5 cubic inches, so almost any keepsake urn will do. By our estimate, a 1 oz keepsake can still cost about a third more than a full-size wooden urn[3], so compare prices. Your local page and the poll results help with the rest.
Worked examples
Urn sizes for five exotic pets, side by side
| Pet | Weight | Volume needed | What to look for |
|---|---|---|---|
| Sugar glider | 140 g (0.3 lb) | About 0.3 cu in (6 mL) | A pendant-size vial or the smallest keepsake |
| African pygmy hedgehog | 450 g (1 lb) | About 1.1 cu in (18 mL) | A single keepsake urn with room to spare |
| Pet skunk | 4 kg (9 lb) | About 10 cu in (159 mL) | A small urn, under the 20 cu in band |
| Bennett's wallaby | 16 kg (35 lb) | About 39 cu in (635 mL) | A medium urn (around 60 cu in) |
| Emu | 40 kg (88 lb) | About 97 cu in (1.6 L) | A large urn (around 120 cu in) |
A hedgehog lives around 4-6 years[4] and leaves enough ash for one keepsake urn. A glider's ashes would rattle around in even that. For the smallest animals, look at glass vials, small lockets or pendant urns, and ask the crematory whether they return ashes in a sealed bag you can transfer.
Beyond size
Choosing a container that suits the animal you kept
Size is only the start. Many exotic keepers want something that reflects the animal: a small wooden box with a branch carving for a glider, a leaf-green glaze for a tree frog, a clear glass vial beside a framed molt. One industry report puts personalised pet urns at about USD 50–1,000+[5], so there's room for simple and special.
Most people keep ashes at home. In one US consumer survey on human remains, 37%[6] of people said they'd keep ashes at home in an urn, and pet ashes often end up on the same kind of shelf. If you plan to scatter or bury instead, a biodegradable container may make more sense; the aftercare options comparison sets those choices side by side.
Where are (or will be) your pet's ashes?
Tap an answer to vote and see how others answered. Anonymous.
Sharing, and what the tool can't know
Sharing small amounts, and the limits of any size estimate
If several people want a share, tick keepsakes and the calculator sets aside about 3 cubic inches per person before sizing the rest. That's more than a hedgehog or glider leaves in total, so for small exotics the tool will tell you the keepsake urns hold everything and no main urn is needed. It doesn't plan pendants; for a glider, a few pendants or one tiny vial will hold almost everything. The ashes sharing planner goes into this in more detail.
Free tool
Ashes sharing planner
Split ashes fairly between family members, keepsake urns and jewelry.
The tool can't tell you exactly how much ash your provider will return, since that depends on the skeleton and how carefully small fragments are collected. For a realistic range first, run the ashes weight estimator. Don't buy an expensive urn until you know roughly what's coming.
What next
Getting the urn and the cremation arranged together
Many crematories can supply a small keepsake urn at the same time as the cremation, which saves transferring ashes yourself. Ask what sizes they stock, as some only carry dog-and-cat sizes. Our memorial ideas for exotic pets has more container ideas.
Or tell us your pet's species and weight and we'll check which providers near you can return ashes in a container that fits. The services page explains what each cremation option includes.
Reader polls
What would you choose?
Vote anonymously and see how other readers answered. The results are live counts from people who visit this site, so they show real opinions, not a scientific sample.
What would you most want to keep from your exotic pet?
Tap an answer to vote and see how others answered. Anonymous.
Where are (or will be) your pet's ashes?
Tap an answer to vote and see how others answered. Anonymous.
What personal touch matters most on a memorial?
Tap an answer to vote and see how others answered. Anonymous.
Free tools to help you plan
Urn size calculator
Find the urn volume you need from your pet's weight, plus keepsake and sharing options.
Ashes sharing planner
Split ashes fairly between family members, keepsake urns and jewelry.
Ashes weight estimator
See roughly how much ash to expect back, by species and body weight.
Questions people ask
What size urn does a hedgehog need?
Only about 1 cubic inch, or roughly 18 mL, for an average African pygmy hedgehog of around 450 g. A standard keepsake urn of about 3 cubic inches holds that with plenty of room. You don't need a full-size pet urn, which would be many times too big.
Can I put a sugar glider's ashes in a pendant?
Often, yes, at least partly. A glider leaves only a few grams, and a pendant holds around 0.05 cubic inches, about a pinch. Depending on your glider's size, the whole amount would fill several pendants, or one tiny vial. A jeweller or the crematory can help you fill it.
Do I need an urn for a tarantula?
Usually not. Tarantulas and other invertebrates rarely leave any recoverable ash, because their exoskeletons burn away. Keepers more often choose a resin piece, a display case or a framed molt. If you want a symbolic container, a small box holding the molt or a favourite piece of cork bark works beautifully.
Is it better to buy the urn from the crematory or separately?
Either is fine. Buying from the crematory saves transferring the ashes and ensures the size fits. Buying separately gives you more choice, especially for very small or very unusual designs. If you buy your own, tell the crematory so they return the ashes in a sealed bag you can transfer.
Sources and our estimates
- [1] Using the industry rule of thumb of 1 cubic inch of urn space per pound of body weight, a 12 lb cat needs an urn of about 12 cubic inches; a 70 lb dog needs about 70 cubic inches. Our estimate: urn cu in = body weight lb x 1 (industry rule of thumb, not a measured value). How we calculate.
- [2] Embrace notes cremated remains typically weigh about 3-5% of the pet's original body weight. Embrace Pet Insurance - Bury or Cremate Your Dog? Costs, Pros & Cons, 2025.
- [3] A 1 oz keepsake urn can cost about a third more than a full-size wooden urn at the same crematory. Our estimate: CA$106 heart keepsake / CA$79 solid wood urn. How we calculate.
- [4] African pygmy hedgehogs live an average of 4-6 years; adult males weigh 400-600 g and females 300-400 g. Merck Veterinary Manual - Overview of Hedgehogs.
- [5] Personalized pet urns range from about USD 50 to more than USD 1,000. Astute Analytica via GlobeNewswire — Global Pet Preservation Services Market to Hit USD 112.7 Million by 2032 (Apr 2, 2024), 2024.
- [6] In NFDA's 2025 consumer research, 37% said they would keep cremated remains at home in an urn, and 33.5% would scatter them. Cremation.Green summary of NFDA 2025 Cremation & Burial Report, 2025.
Get cremation and a fitting urn sorted together
Tell us what you need and where you are. We'll reply by email with clear options and prices so you can decide in your own time.