Free tools to plan a fish's goodbye, from ash to budget
Ash is usually about 3-5% of body weight[1], so a koi and a betta produce wildly different results. These six tools do the math for your fish in under a minute.
- Works in your browser, nothing to download
- Ranges shown with their sources
- Built for fish sizes, not just dogs
Where to start
Which tool should you use first?
If you're deciding whether cremation is worth it for your fish, start with the ashes weight estimator. It tells you whether you'll get enough back for an urn, a pendant or nothing you could collect. Everything else follows from that answer.
If you already know you want ashes back, the cost calculator and urn size calculator come next. And if you want to see the whole bill, including a pond marker or keepsake glass, finish with the memorial budget planner.
Every tool works on your phone, needs no account and shows results as you type. They give ranges, not quotes. When you want actual prices, send us your fish's details.
Tool 1
Ashes weight estimator: will there be anything to keep?
Enter your fish's weight and see the likely ash range. A 10 lb koi might return around 5 to 8 ounces. A fancy goldfish returns a pinch. A tetra may return nothing you could separate. The tool also gives you an everyday comparison, so the numbers feel real.
Free tool
Ashes weight estimator
See roughly how much ash to expect back, by species and body weight.
Read more on the ashes weight estimator page, including a worked koi example.
Tool 2
Cremation cost calculator: a realistic price range
Choose communal, private or witnessed cremation, your country and any extras like home collection. The calculator returns a low-to-high range built from published price guides. For fish, the smallest weight band almost always applies.
Free tool
Cremation cost calculator
Estimate a realistic price range for your pet's size, location and the type of cremation.
The average US pet cremation was about USD 250[2] in one industry review, but that average includes large dogs. The cost calculator page explains why fish usually cost less, and when they don't.
Tool 3
Urn size calculator: from koi urn to keepsake vial
Urns are sold by volume in cubic inches, and the usual rule is one cubic inch for every pound of body weight. Our worked example of that rule gives a 12 lb cat an urn of about 12 cubic inches[3], so by the same estimate an 8 lb koi needs about 8, and most fish need a keepsake-size urn at most. Enter the weight and how many people want a share, and the calculator suggests a size.
Free tool
Urn size calculator
Find the urn volume you need from your pet's weight, plus keepsake and sharing options.
Tool 4
Aftercare options compared: cremation, burial or water?
Slide the priorities that matter to you, such as cost, keeping ashes, environmental impact or a ceremony, and the tool ranks private cremation, communal cremation, water cremation, home burial and pet cemeteries. For small fish, burial often comes out on top, and that's fine.
Free tool
Aftercare options compared
Compare private, communal and water cremation with burial on cost, timing and what comes home.
Environmental impact is a real concern for many: 40%[4] of consumers raise it about pet aftercare, according to one market analysis. Our environmental claims guide helps you weigh them, and the Veterinary Sustainability Alliance's aquamation explainer describes how water cremation works.
Tool 5
Ashes sharing planner: splitting a koi's ashes fairly
When a family koi dies, more than one person may want a share: a parent, a grown child who fed it as a toddler, a neighbor who fish-sat every summer. The planner splits the ashes between keepsake urns, pendants and rings, and shows what's left for the main urn.
Free tool
Ashes sharing planner
Split ashes fairly between family members, keepsake urns and jewelry.
Tool 6
Memorial budget planner: the whole goodbye, added up
Add cremation, collection, an urn, keepsake glass, a pond-side stone and a new water lily, adjust each amount and see a running total. It's useful when a koi's memorial is shared between family members, or when you want to know where to save.
Free tool
Memorial budget planner
Add up cremation, urn, keepsakes and a farewell so the total holds no surprises.
Money is on most people's minds here. In one US survey, 61%[5] of owners rated the cost of aftercare as a concern. The budget planner page includes a worked koi memorial, and our services page explains every option in detail.
How much would you spend on a memorial item, beyond the cremation itself?
Tap an answer to vote and see how others answered. Anonymous.
Read before you rely on a number
What these calculators can and can't tell you about a fish
The tools are built on published figures for pets in general, because we haven't found a published study of what koi or goldfish leave after cremation. We think that's worth saying plainly. The 3 to 5% ash rule comes from mammals with heavy skeletons. The best-known measurement, a forensic study of 100 human cremations, found adult remains averaged about 3.5%[6] of body weight, so treat the fish result as an upper guide.
| Fish | Weight entered | What the tools suggest |
|---|---|---|
| Twenty-year-old koi | 12 lb | Roughly 6 to 10 oz of ash, a small urn plus a few keepsakes |
| Pond comet goldfish | 1 lb | About half an ounce, one keepsake vial |
| Betta | 0.1 oz | Too little to measure; consider burial or a memorial |
What the tools can't do: tell you whether a particular provider accepts fish, what they'll charge on a weekend, or how your family will feel about each option. Those answers come from a phone call and a conversation at home. When you're ready, our contact page explains what to send, and the symbolic ash yield guide covers what to ask about very small fish.
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 choose for a fish you loved?
Tap an answer to vote and see how others answered. Anonymous.
How much would you spend on a memorial item, beyond the cremation itself?
Tap an answer to vote and see how others answered. Anonymous.
What would you expect to pay for private cremation of a medium-size dog?
Tap an answer to vote and see how others answered. Anonymous.
Free tools to help you plan
Ashes weight estimator
See roughly how much ash to expect back, by species and body weight.
Cremation cost calculator
Estimate a realistic price range for your pet's size, location and the type of cremation.
Urn size calculator
Find the urn volume you need from your pet's weight, plus keepsake and sharing options.
Aftercare options compared
Compare private, communal and water cremation with burial on cost, timing and what comes home.
Ashes sharing planner
Split ashes fairly between family members, keepsake urns and jewelry.
Memorial budget planner
Add up cremation, urn, keepsakes and a farewell so the total holds no surprises.
Questions people ask
Are these tools accurate for fish?
They use general pet figures, such as ash at about 3 to 5% of body weight, and published price guides. Fish can fall at the low end for ash because their skeletons are light. Treat the results as a starting point and confirm with a provider before you book.
Do I need to weigh my fish?
It helps but isn't essential. For a large koi, a bathroom scale works: weigh yourself holding the bagged fish, then without it. For small fish, the length is enough to know you're in the smallest price band and should expect very little ash.
Do the tools save my information?
No. The calculators run in your browser and don't send what you type to us. If you want real quotes, you can choose to send us your details through the form, and only then do we see them.
Why does the cost calculator show a range and not a price?
Because prices vary by provider, city and extras such as home collection. A range built from published guides is honest; a single figure would pretend to know your local market. For an exact price, ask providers for a written total.
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] The average pet cremation cost about USD 250 (Foresight Companies, 2020). The Foresight Companies — Industry Spotlight: The Pet Business (2020), 2020.
- [3] 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.
- [4] Astute Analytica reports that 40% of consumers raise environmental concerns about pet aftercare choices. Astute Analytica via GlobeNewswire — Global Pet Preservation Services Market to Hit USD 112.7 Million by 2032 (Apr 2, 2024), 2024.
- [5] 61% of US owners in the Cooney survey rated the cost of after-death body care as a concern (27.9% concerned, 33.1% very concerned). Cooney, Kogan, Brooks, Ellis - Pet Owners' Expectations for Pet End-of-Life Support and After-Death Body Care, Topics in Companion Animal Medicine (2020), 2020.
- [6] In a study of 100 commercial human cremations, cremated remains averaged about 3.5% of total body weight in adults, 2.5% in children and about 1% in fetuses; this is the benchmark most pet crematories adapt for animals. Warren MW, Maples WR. The anthropometry of contemporary commercial cremation. Journal of Forensic Sciences, 1997 (PMID 9144931), 1997.
- [7] Nishikigoi (koi) typically live about 30 to 40 years depending on their environment. All Japan Nishikigoi Promotion Association - Ancient koi 'Hanako', 2024.
Want exact prices, not estimates?
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.