What size urn does your reptile need?
Cremated remains weigh about 3-5% of body weight[1], so a bearded dragon's ashes fit in a thimble-sized space while a big tortoise needs a real urn. Enter the weight and see exactly what to buy.
- Volume in cubic inches and millilitres
- Keepsake sizes for tiny amounts
- Sharing between family members built in
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 →
Using it
Three inputs, one clear answer
Enter your reptile's body weight in pounds or kilograms. Then say how many people will share the ashes (one to eight) and whether each person wants a keepsake urn of about 3 cubic inches. The tool shows the main urn volume in cubic inches and millilitres, a suggested standard size and the volume set aside for keepsakes.
Use the weight from the last time you weighed your reptile if you can; a kitchen scale is fine for anything under a few pounds. If you only know length, as with many snakes, ask your vet for a weight at the next check or use a rough estimate and round up.
The maths
How the calculator works out volume
Urn makers use a simple rule: allow about one cubic inch of space for every pound of body weight. The calculator applies that rule and adds a 10% margin so the ashes and their bag fit comfortably without packing. One cubic inch is a little over 16 mL.
It then matches your result to standard urn sizes: small (around 20 cubic inches), medium (60), large (120) and extra-large (200 or more). Anything up to 20 cubic inches is labelled small, so most reptiles land there, and for animals under 2 lb the tool adds a note that a keepsake-sized urn is often enough. Read a result of a few cubic inches as keepsake size, because a standard urn would be almost empty.
| Reptile and weight | Volume needed | Suggested container |
|---|---|---|
| Leopard gecko, 60 g (0.13 lb) | About 0.1 cu in (2 mL) | Pendant or small glass vial |
| Bearded dragon, 450 g (1 lb) | About 1.1 cu in (18 mL) | Keepsake urn |
| Ball python, 4 lb | About 4.4 cu in (72 mL) | Large keepsake urn |
| Green iguana, 12 lb | About 13 cu in (216 mL) | Small urn |
| Sulcata tortoise, 100 lb | About 110 cu in (1.8 L) | Large urn |
Example
Worked example: a 4 lb ball python shared by two people
A 4 lb ball python needs about 4.4 cubic inches in total. If you and a sibling both want some, set sharing to two and leave keepsakes unticked: the tool splits the ashes into two shares of 2 cubic inches and suggests about 2.2 cubic inches (36 mL) each, keepsake-urn territory. Tick keepsakes as well and it reserves 3 cubic inches per person, more than the python's whole 4, so it tells you the keepsake urns hold everything. Pendants aren't part of this calculator; take a pinch from either share if you'd like one. Neither of you needs a full-size urn.
One industry report puts personalised urns at about USD 50–1,000+[2], so knowing you only need a keepsake can save a surprising amount. If more people want a share, the ashes sharing planner allocates pendants, vials and keepsake urns in more detail.
For a small lizard or gecko, would you still choose private cremation knowing only a pinch of ash may come back?
Tap an answer to vote and see how others answered. Anonymous.
Your result
What the result means for a snake, lizard or tortoise
If the result is only a few cubic inches, a full urn would look nearly empty and may rattle. Look instead at small ceramic keepsakes, glass vials, lockets or a shadow box with a compartment, which can hold a shed skin as well. If it's in the tens of cubic inches, the size shown includes the margin, so buy that size or the next one up. If you want a name and dates engraved, budget for it: by our estimate, engraving adds about 36% to the price of a mid-priced wooden pet urn.[3]
Tortoises can return a little more than the rule predicts, because the shell is bone. If you're between sizes for a chelonian, round up. For all reptiles, check how much ash you're likely to get with the ashes weight estimator.
40%+[4]
Honest limits
What the calculator can't tell you
- The exact volume you'll receive. Ash density varies with the animal and the provider's processing. The rule is a sizing guide, not a measurement.
- Whether a provider returns ashes in their own container. Many include a basic box or pouch; you may not need to buy anything straight away.
- Water cremation returns. Aquamation tends to return slightly more remains than flame, so allow extra room.
- Planting. If you plan to mix ashes into soil, remember they're strongly alkaline, with a pH of ~11.7[5], and need amending before plants will cope.
Many families don't keep ashes in an urn at all. In a summary of NFDA's 2025 consumer research on human remains, 37%[6] said they'd keep them at home in an urn, and about a third would scatter them. If scattering appeals, our scattering guide explains where you can and can't.
What next
Next steps once you know the size
Before buying, ask the crematory what container they return ashes in and whether they sell small urns themselves. For ideas beyond an urn, see memorial ideas for reptile keepers. If you haven't arranged cremation yet, the services page explains the options, or tell us about your reptile and we'll email you local providers. If you plan to bury the urn in a pet cemetery in England, the GOV.UK rules for pet cemeteries explain the registration they need. To check the cost of the cremation itself, try the cremation cost calculator; private vs communal cremation explains which option returns ashes, and our local pages show typical prices near you.
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.
For a small lizard or gecko, would you still choose private cremation knowing only a pinch of ash may come back?
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.
Which memorial feels most like your pet?
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 do I need for a bearded dragon?
Very small. A typical adult bearded dragon weighs around a pound, which works out to about one cubic inch of space. A keepsake urn of 2 to 5 cubic inches holds everything comfortably, with room for a small keepsake such as a shed or a note.
Can I use a standard pet urn for a snake?
You can, but for most pet snakes it will be far too big. A 4 lb ball python needs under 5 cubic inches, while a small standard urn is around 20. Very large pythons and boas are the exception and may need a medium or large urn.
How much bigger should a tortoise urn be?
Size it by weight like any other reptile, then round up to the next standard size if you're close to a boundary. The shell is bone and can make the returned volume a little larger than the one-cubic-inch-per-pound rule suggests.
Is it okay if the urn has extra space?
Yes. Ashes are usually returned in a sealed bag, which sits inside the urn, so extra space doesn't matter. Some families add a note, a shed skin or a small photo to fill it. The only problem is an urn that's too small.
Sources and our estimates
- [1] 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.
- [2] 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.
- [3] Name-and-dates engraving adds about 36% to the price of a mid-priced wooden pet urn. Our estimate: midpoint engraving $32.50 ($25–$40) / midpoint wood urn $90 ($30–$150). How we calculate.
- [4] Pet urns generated over 40% of pet memorial product revenue in 2023. DataHorizzon Research — Pet Memorials Market report page, 2023.
- [5] Cremated remains have a very high pH of approximately 11.7, which is toxic to plants without amendment. Larkspur Conservation — Giving Cremated Remains a New Life Through Science, 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.
Want help choosing an urn and a provider?
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.