Pet-store bettas are often already 6–12 months old when you buy them (Chewy, vet-reviewed). On farms, young bettas are reared together until 3–4 months, then males grow alone for 8–12 more weeks before export (UF/IFAS). So a betta you've had for a year is probably 1.5–2 years old.
General information only. Vets publish few betta figures, so we combine vet, university, database and peer-reviewed sources and say which is which; pet-care sites are used only to fill gaps. For a sick or injured betta, see an aquatic (fish) vet. We give no medication advice.
How old are betta fish when you buy them?
Usually somewhere between six months and a year. Chewy's vet-reviewed guide says "the betta you bring home could already be 6–12 months old", and adds that you often get no information about a shop betta's age or genetics. That range fits what UF/IFAS describes on commercial farms, where a male betta spends months growing before it is ever packed for export.
So when you ask how old are betta fish when you buy them, the honest answer is "probably older than you think — but nobody wrote it down". The calculator adds the typical 6–12 months to the time you've had your fish, or uses the exact age if the breeder told you.
From farm to shop: the betta's journey
UF/IFAS gives the clearest description of how pet-store bettas are produced. Breeding pairs spawn in small containers; the female releases eggs, the male places "about 300 eggs" in a bubble nest and guards them. Once the larvae have used their yolk sacs, about three days after hatching, they go to grow-out tanks. The young are reared together until 3–4 months old, "at which point the males become distinguishable from females and must be separated". Males then grow in individual bottles for another 8 to 12 weeks, depending on the size and fins buyers want.
| Step | Age or time | Notes |
|---|---|---|
| Spawning | Day 0 | About 300 eggs in a bubble nest (UF/IFAS) |
| Hatching | 1–2 days | Eggs hatch 24–48 hours after spawning (ADW) |
| Free-swimming fry | About 3 days after hatching | Moved to grow-out tanks (UF/IFAS) |
| Group rearing | To 3–4 months | Then males are separated (UF/IFAS) |
| Males in bottles | A further 8–12 weeks | Grown for size and fins (UF/IFAS) |
| Shipping and shop | Days to weeks | Air freight, wholesaler, then retailer (UF/IFAS) |
| Typical age when sold | 6–12 months | Chewy (vet-reviewed) |
Add those steps together and a male typically leaves the farm at roughly five to seven months — our arithmetic from the UF/IFAS figures, not a published number. Then come air freight (UF/IFAS estimates more than 100,000 males a week, mostly from Thailand), a wholesaler and the shop shelf. That's how a fish ends up 6–12 months old by the time it reaches your tank.
How old are bettas at PetSmart and other chain stores?
We couldn't find any official statement from PetSmart, Petco or other chains about the age of their bettas, so how old are bettas at PetSmart can only be answered from the supply chain. Big retailers sell mass-produced bettas from the same kind of Southeast Asian farms UF/IFAS describes, so the general 6–12 month range is the best estimate. Some shops sell "baby" bettas, which are younger and smaller, but we found no reliable source for their exact age — use the size and colour cues on our betta age chart instead.
If you buy from a breeder, ask for the spawn date. Breeders usually know it to the week, and you can enter the exact age in the calculator for a much better answer.
Why the age at purchase matters
A betta's lifespan is counted from hatching, not from the day you bring it home. With a typical lifespan of 3–5 years, a fish bought at 6–12 months has already used about 13–25% of an average 4-year life. For example, a betta you've had for a year is probably 1.5–2 years old, not one.
The journey also takes a toll. A 2025 study shipped male bettas for two days by road without food and found they needed about 8 days to recover their weight, colour and condition. Chewy warns that shop conditions — "overcrowded tanks or too-small individual cups" — may shorten a fish's life, and a 2024 welfare study recommended at least 5.6 litres for bettas on display or sale, far more than a typical cup. Give a new fish a quiet, warm, clean tank and a week or so to settle.
Picking a healthy betta in the shop
You can't read an age on the label, but you can check health. Chewy suggests starting with "the healthiest fish possible" and seeing the specific fish in person if you buy from a breeder. Use the illness signs Unusual Pet Vets list as a checklist and avoid fish that show them:
- Colour: strong and even, not faded or patchy.
- Fins: whole and spread, not thin, ragged or clamped tight to the body.
- Body: no weight loss, sunken belly, white spots or fuzzy patches.
- Behaviour: alert and responsive, not lying on the bottom of the cup.
- Cup: clear water, without a layer of uneaten food or waste.
How this age-at-purchase calculator works
Enter how long you've had your betta and, if you know it, its age when you bought it. If you leave that blank, the calculator shows a range using Chewy's 6–12 months. It then compares the estimated age with the same 3–5 year lifespan the betta fish lifespan calculator uses, and suggests an age to enter there for years left and a care score.
Frequently asked questions
How old are betta fish when you buy them?
Often 6–12 months old, according to Chewy's vet-reviewed guide. Shops rarely know the exact age.
How old are bettas at Petco?
Petco hasn't published an age. Chain-store bettas come from the same kind of farms UF/IFAS describes, so the general 6–12 month estimate applies.
How old is a betta in a cup at the pet store?
Usually an adult of several months. Males are reared in groups until 3–4 months, then grown alone for 8–12 more weeks before shipping (UF/IFAS).
How old are baby bettas in stores?
We found no reliable source for their age. They are younger than standard bettas; use size, fins and colour to estimate it on our betta age chart.
How do I find out my betta's real age?
Ask the seller or breeder for a spawn date. Without one, add 6–12 months to the time you've had it — that's what this calculator does.
Why do shop bettas die so soon?
Their lifespan started months before you bought them, and shipping and small cups are stressful. Shipped bettas needed about 8 days to recover from a 2-day trip (Thongprajukaew et al. 2025).
If I've had my betta for 2 years, how old is it?
Probably 2.5–3 years, if it was a typical 6–12 months old when you bought it. That is the start of the 3–5 year range.
Are bettas from breeders younger?
Not necessarily, but breeders usually know the spawn date, so you can enter an exact age instead of a range.
This calculator gives an estimate for education and fun. Every pet ages differently — for health decisions, talk to your veterinarian.