Published October 26, 2026 · The Cricket Depot, San Antonio, Texas
Cricket sellers use size names like pinhead, small, medium, large and adult, but those labels are not standardized across the industry. One farm's "medium" may be a little bigger or smaller than another's. This guide explains how we size our house crickets, what changes as crickets grow and how to choose a size that your animal can eat safely and comfortably.
Why size matters
Feeding the wrong size causes more problems than most people expect. A cricket that is too big can be hard to swallow, and keepers commonly worry about choking or digestive trouble when prey is oversized. A very large adult cricket also has a tougher exoskeleton and stronger legs. Crickets that are too small are not dangerous, but your animal has to chase and eat many more to get a meal, which wastes time and money and can leave a larger animal underfed.
A widely used rule of thumb is that a feeder insect should be no longer than the space between your animal's eyes. It is not a precise measurement, but it is a sensible starting point.
The five sizes we sell
House crickets (Acheta domesticus) grow by molting, shedding their skin several times on their way to adulthood. We sort them by approximate age and length. Times depend heavily on temperature, so treat these as approximate:
- Pinhead: newly hatched, up to about a week old, under about 1/8 inch. Tiny, pale and delicate.
- Small: around two weeks old, roughly 1/4 inch.
- Medium: around three to four weeks, roughly 1/2 inch. Our most requested size.
- Large: around five to six weeks, roughly 3/4 inch. Wing buds are often visible.
- Adult: six to seven weeks and older, about 3/4 to 1 inch, with full wings. Adult males chirp.
Our size chart shows the same information in a table you can keep handy.
Which size for which pet
These are general matches; your individual animal's size is what really decides it.
- Pinheads: hatchling geckos and other tiny lizards, froglets, dart frogs, very small spiderlings and mantis nymphs.
- Small: baby bearded dragons, baby leopard geckos, young chameleons, juvenile frogs and small tarantulas.
- Medium: juvenile bearded dragons, juvenile and smaller adult leopard geckos, many tree frogs and mid-size spiders.
- Large: adult leopard geckos, young adult chameleons, larger frogs and juvenile tarantulas of bigger species.
- Adult: adult bearded dragons, large tarantulas, monitor juveniles and large frogs such as horned frogs.
When an animal sits between two sizes, many keepers choose the smaller one and feed a few more. That errs on the side of safety.
How quickly crickets "size up"
Crickets keep growing after they arrive, especially if they are warm and well fed. A batch of small crickets kept at room temperature for two weeks may be closer to medium by the time you finish it. That can work in your favor if your pet is growing too, but if you need a specific size for a small animal, order quantities you can use within a week or two, or keep them a little cooler to slow growth (still within a safe temperature range).
Adults, on the other hand, are at the end of their growth and have a limited remaining lifespan. If you buy adults, plan to use them sooner.
Pinheads need extra care
Pinheads are the most fragile size. They dehydrate quickly, drown easily in even a thin film of water and can slip through gaps that hold larger crickets. Keep them in a container with fine ventilation, offer moisture through water gel or thin vegetable slices rather than anything wet, and give them a powdered or finely ground food they can actually eat. Expect them to be harder to see and to count.
Adults: pros and cons
Adult crickets offer the most food per insect, which suits larger animals. They are also the size that chirps, and males can be noisy at night. Adults are stronger, jump farther and are more likely to hide in an enclosure if not eaten right away, so remove leftovers after a feeding. Some keepers remove the large hind legs before feeding to small or cautious animals, though many feed them whole without issue.
Size and nutrition
People sometimes ask whether one size is "healthier" than another. In general terms, the nutrition of a cricket depends more on how it was raised and what it recently ate than on its size label. Smaller nymphs have a higher proportion of soft body to exoskeleton, while adults have tougher shells and wings, which some keepers feel are harder for small animals to digest. Larger crickets simply deliver more food per insect. For most pets, the right approach is to pick the size that matches the animal, feed a sensible number and gut-load well before feeding. A well-fed medium cricket is a better meal than a starving adult. If your vet has given you specific advice about prey size for your animal, follow that over any general chart, including ours.
Buying tips
- Measure your animal: eyeball the gap between its eyes and compare with the lengths above.
- Buy for the next few weeks, not the next few months: crickets grow and age.
- Mixed animals? If you keep a baby and an adult, it can make sense to split an order across two sizes.
- Ask us: text a photo of your pet to (210) 461-9760 and we will suggest a size.
Once you have the right size, keeping them healthy is the next step. See how to keep crickets alive and odor-free, and for portions, how many crickets to feed.