You just got a jumping spider, or you’re about to, and the first real question is always the same: what do jumping spiders eat, and how do I actually feed one tonight?
The short answer is live insects. But that covers a lot of ground. Not all feeders are equal in nutrition, safety, or ease of sourcing. This guide tells you exactly which feeders to use at each life stage, how large prey should be, how often to feed, what to never offer, and where to get feeders without any guesswork.
Key Takeaways
- Jumping spiders are insectivores that need live prey. They rarely accept dead or frozen insects.
- Prey should be no larger than half the spider’s body length. When in doubt, go smaller.
- Fruit flies (Drosophila hydei) are the safest, easiest feeder for juveniles and small adults.
- Adults eat every 3-5 days. Juveniles eat every 2-3 days. Spiderlings eat every 1-2 days.
- Gut-load feeders 24 hours before offering them. What the feeder ate, your spider eats.
- Remove any uneaten prey within 24 hours. Crickets in particular can injure a resting spider.
- Never feed within 48 hours of a molt. A freshly molted spider’s fangs and body are still soft.
What do jumping spiders eat: the quick answer
Jumping spiders are obligate carnivores. In the wild they hunt flies, moths, mosquitoes, and whatever else moves across their path. In captivity, the best staple feeders are:
- Fruit flies (Drosophila hydei or D. melanogaster): ideal for spiderlings through small adults
- Bottle flies (blue or green): excellent for sub-adults and adults, high protein and very stimulating
- Small crickets: widely available, good protein source, works for most life stages
- Dubia roaches: the best all-round nutritional profile; easy to store, cannot climb glass
- Mealworms: available everywhere but high in fat. Use as an occasional treat, not a staple
That list covers 95% of what you will ever need. Waxworms, moths, and superworms are enrichment items, not staples.
Feeder comparison: which bug is right for your spider?
| Feeder | Nutrition | Availability | Storage ease | Best for |
|---|---|---|---|---|
| Fruit flies (D. hydei) | Moderate; gut-load to boost | Online, some pet stores | Easy: room temp in culture cup | Spiderlings, juveniles up to ~1.5 cm |
| Bottle flies (blue/green) | High lean protein | Online specialty shops | Moderate: pupae in fridge up to 4 weeks | Sub-adults and adults |
| Crickets | Good protein, variable fat | Most pet stores | Moderate: ventilated cricket keeper | Juveniles to adults; remove uneaten ones |
| Dubia roaches | Excellent: high protein, low fat, calcium-rich | Online, some reptile stores | Very easy: tub at 24°C | Any life stage large enough to take them |
| Mealworms | High fat, lower protein | Most pet stores | Very easy: fridge at 10°C | Occasional treat only, 1-2 per month |
| Waxworms | Very high fat | Some pet stores, online | Easy: fridge | Enrichment only; great for picky eaters |
Prey size: the rule that matters most
Offer prey no larger than half the spider’s body length (measure body only, not legs).
A spider with a 2 cm body should get prey no bigger than 1 cm. Spiders can occasionally overpower larger prey, but oversized feeders cause stress, injury, and real danger during and just after a molt.
When in doubt, go smaller. Two small crickets deliver more enrichment and less risk than one cricket that is too large.
Size guide by life stage
| Life stage | Body length | Recommended feeder | Target feeder size |
|---|---|---|---|
| Spiderling (instar 3-4) | 3-6 mm | D. melanogaster fruit flies | 1-2 mm |
| Juvenile (instar 5-6) | 6-12 mm | D. hydei fruit flies, micro crickets | 3-5 mm |
| Sub-adult | 12-18 mm | Small crickets, bottle flies, small dubia | 5-8 mm |
| Adult female | 15-22 mm | Crickets, bottle flies, dubia roaches | 7-10 mm |
| Adult male | 12-18 mm | Crickets, bottle flies | 5-8 mm |
Watch your spider’s reaction. If it retreats from prey or ignores it for more than 10 minutes, the prey is probably too large or your spider is not hungry. Remove the feeder immediately.
Fruit flies: the beginner’s best feeder
If you are new to keeping jumping spiders, start here. Fruit flies cannot bite, cannot injure your spider, and are available in cultures that last 3-4 weeks. They are the safest possible first feeder.
Two species you will see sold:
- Drosophila melanogaster (“mels”): tiny, roughly 1-2 mm. Use for spiderlings and very small juveniles.
- Drosophila hydei (“hydei”): larger, roughly 3 mm. Use for juveniles and smaller adults.
Both come as flightless cultures: the flies cannot fly, so feeding is far less chaotic than you might expect. A single culture produces hundreds of flies over 3-4 weeks.
Gut-loading fruit flies: tip the culture cup into a small container with mashed banana, bee pollen, or commercial fly media 24 hours before feeding. Gut-loading means giving the feeders nutritious food before they become your spider’s meal. Your spider then benefits from what the feeders ate. This one step meaningfully improves every feeding.
How to feed: place the culture cup on its side inside the enclosure and let 5-10 flies walk in, then cap it back up. Alternatively, chill the culture in the fridge for 10 minutes to slow the flies, then drop them in individually with soft-tip tweezers.
Crickets: available everywhere, handle with care
Crickets are the feeder most people reach for first because every pet store carries them. They work well, but with one important rule: remove any cricket your spider has not eaten within 24 hours.
Crickets bite. An unattended cricket will harass and injure a resting or molting spider. Remove any uneaten crickets before your spider settles in for the night.
Beyond that caveat, crickets are a solid staple: good protein, active enough to trigger a strong hunt response, available in every size from pinhead to adult. For most adult jumping spiders, a cricket roughly 7-8 mm long offered every 3-5 days is a reliable baseline.
Dubia roaches: the keeper favourite
Experienced keepers consistently rate dubia roaches (Blaptica dubia) as the best feeder for arachnids. They are soft-bodied, cannot climb smooth glass or acrylic, do not make noise, and have an excellent nutritional profile: high protein, moderate fat, more calcium than crickets.
The only downside is availability. Most local pet stores do not carry them. Order online and keep a small bag of mixed-size nymphs at around 24°C. They are easy to maintain.
Offer nymphs sized to half the spider’s body length. A small dubia nymph of 5-7 mm works well for a typical adult jumping spider. Gut-load with carrot, dark leafy greens, or dry oats for 24 hours before feeding.
Bottle flies: the best feeder for adults
Blue bottle flies (Calliphora vomitoria) and green bottle flies (Lucilia sericata) are sold as pupae you keep in the fridge. Take out a small handful at room temperature and they hatch in 1-3 days. This lets you control exactly how many flies emerge at once.
For adult jumping spiders, bottle flies are hard to beat. They are fast-moving, which triggers the strongest hunt response. They are also large enough to constitute a full meal, and unlike crickets they cannot injure your spider. Two or three bottle flies every 3-5 days is a complete adult diet on its own.
How often to feed your jumping spider
Jumping spiders have fast metabolisms when young, which slow down as adults.
| Life stage | Feeding frequency | Prey items per feeding |
|---|---|---|
| Spiderling (instar 3-5) | Every 1-2 days | 3-5 D. melanogaster |
| Juvenile (instar 5-7) | Every 2-3 days | 5-8 D. hydei or 1 micro cricket |
| Sub-adult | Every 2-3 days | 1 small cricket or 2-3 bottle flies |
| Adult | Every 3-5 days | 1 cricket, 2-3 bottle flies, or 1 small roach |
Signs your spider is hungry: actively patrolling the enclosure walls, tracking every movement with those big forward-facing eyes, alert posture and quick turns.
Signs your spider has had enough: retreating from prey, turning away from offered insects, ignoring prey for 10+ minutes.
Never feed within 48 hours of a molt. A freshly molted spider’s exoskeleton is soft for 48-72 hours. Wait until your spider has resumed normal movement and the chelicerae look dark again before offering food. See the jumping spider molting guide for the full molt timeline.
What to do in the week after a molt
Wait 48-72 hours. That is the whole plan. The new exoskeleton needs time to harden completely.
Once your spider resumes normal activity:
- Offer one prey item that is clearly on the smaller end of the normal size range
- Watch the full interaction and remove it after 10 minutes if ignored
- Return to your normal schedule from the next feeding session onward
A post-molt fast of 1-2 weeks before the molt, plus 48-72 hours of hardening afterward, is entirely normal. Do not panic and do not rush it.
Can jumping spiders eat dead or pre-killed prey?
Most jumping spiders refuse dead prey entirely. Their vision is built to detect movement, and a motionless insect simply does not register as food to most individuals.
A small number of well-established adults will eventually accept pre-killed prey if you wiggle it with tweezers to simulate movement. If you want to try it: use soft-tip tweezers, hold the prey by a leg, and move it gently across the floor of the enclosure. Offer it once. If the spider shows no interest within a few minutes, remove it and return to live prey.
Freeze-dried or canned insects are not recommended. The nutritional profile degrades significantly and most jumping spiders will not accept them regardless.
What to do if your jumping spider stops eating
Occasional fasting is normal. Before troubleshooting, check: is your spider pre-molt? Does the abdomen look darker or the spider seem restless and slower? A pre-molt fast of 1-3 weeks is common and nothing to worry about.
Other reasons a spider might refuse food:
- Prey is too large
- The enclosure is too cold (under 18°C slows metabolism)
- Prey was offered at the wrong time (jumping spiders are most active mid-morning)
- The spider just ate recently and is full
Try offering a different feeder type at a different time of day. If your spider refuses food for more than 4 weeks outside of a molt period, check our jumping spider not eating guide for a full troubleshooting list.
Gut-loading and nutrition: why it matters
A cricket that ate cardboard provides far less nutrition than one fed on dark leafy greens and carrot. Gut-loading means feeding your feeder insects well for 24-48 hours before offering them to your spider. Your spider then absorbs whatever the feeder was carrying.
Good gut-load foods by feeder type:
| Feeder | Good gut-load foods |
|---|---|
| Crickets | Dark leafy greens, carrot, dry oats, commercial cricket gut-load |
| Dubia roaches | Carrot, squash, leafy greens, dry dog food |
| Fruit flies | Mashed banana, bee pollen, commercial fly media |
| Mealworms | Bran, carrot, bee pollen |
Avoid citrus, onion, and anything high in oxalates for gut-loading. Keep it simple: carrot and leafy greens cover most of what you need.
Do jumping spiders need calcium or vitamin dusting? For most keepers, no. A well gut-loaded, varied diet provides what they need. Dusting is more relevant for lizards and geckos. If you are concerned about nutrition, focus on gut-loading rather than dusting.
Foods to avoid
| Feeder | Why to avoid |
|---|---|
| Fireflies (Lampyridae) | Toxic. Bioluminescent compounds are lethal to spiders |
| Wild-caught insects | Risk of pesticides, parasites, and unknown pathogens |
| Ants | Formic acid causes chemical burns to the chelicerae |
| Hard-shelled beetles | Injury risk to chelicerae; spider may be hurt before subduing prey |
| Other spiders | Jumping spiders will attempt to eat them, but the encounter is risky |
| Dead insects (unfresh) | Risk of bacteria; low acceptance rate anyway |
Stick to captive-bred feeders from a reputable source and you will not encounter any of these problems.
Where to buy feeder insects
Local pet stores (Petco, PetSmart, independent reptile shops): carry crickets and mealworms reliably. Occasionally carry dubia roaches. Rarely carry fruit fly cultures or bottle fly pupae.
Online specialty suppliers: the better option for fruit flies, bottle flies, and dubia roaches. Search “feeder insects overnight shipping” or “flightless fruit fly cultures.” Multiple suppliers ship with live arrival guarantees. A single fruit fly culture costs $5-8 and lasts 3-4 weeks. Our feeder insects gear guide covers tested suppliers.
Starting order for a juvenile spider: one D. hydei culture, one D. melanogaster culture. That covers 6-8 weeks of feeding while you learn what your spider prefers.
Starting order for an adult spider: one D. hydei culture plus a small bag of 1/4-inch crickets (around 50). That covers the first month and lets you compare which feeder gets the stronger hunt response.
Storing feeders properly
Fruit fly cultures: room temperature (20-25°C), upright, lid loosely on. Do not refrigerate. Cold kills the culture. Flies typically begin emerging within 7-10 days of starting a new cup.
Crickets: ventilated plastic cricket keeper with a toilet-paper roll for hiding. Offer dry oats and a small piece of orange or carrot for moisture. Clean the container every 2-3 days. Dead crickets cause ammonia buildup that kills the batch.
Dubia roaches: plastic tub with ventilated lid at 24-28°C. Feed carrot slices or dry dog food. They produce little odor and are easy to maintain. A bag of 50 nymphs lasts weeks if kept warm and fed.
Bottle fly pupae: sealed in the fridge at 4°C. This pauses development. Take out a small handful, let them reach room temperature, and they hatch in 1-3 days. Check our fruit fly culture setup guide if you want to grow your own.
Quick-start feeding plan for tonight
- If you have a spiderling or juvenile: order D. melanogaster and D. hydei cultures online with overnight shipping. As a bridge tonight, buy 1/8-inch crickets from any pet store and offer one.
- If you have an adult: buy 1/4-inch crickets at any pet store tonight. Offer one cricket and remove it after 30 minutes if ignored.
- Set a feeding reminder every 3 days and adjust based on how eagerly your spider hunts.
- Order a D. hydei culture online this week. It is the most versatile feeder you will use.
For everything else about keeping a jumping spider healthy, the complete jumping spider care guide covers housing, molting, handling, and lifespan in one place. The enclosure setup guide will help you get the habitat ready before your feeders arrive.
FAQ
How long can a jumping spider go without eating? Healthy adults regularly fast for 1-2 weeks, especially before a molt. Some go 3-4 weeks without concern. If your spider has refused food for more than 4 weeks outside a molt, check for pre-molt signs (darker abdomen, sealed retreat) and review enclosure temperature and prey sizing. See the not eating guide for a full checklist.
Can jumping spiders eat fruit or vegetables? No. Jumping spiders are obligate carnivores. They do not eat plant matter in any meaningful way. Some individuals will sip diluted fruit juice or water off a wet sponge, but fruit and vegetables are not a food source for them.
Do jumping spiders need vitamin or calcium supplements? Not if you gut-load your feeders properly. A varied diet of well-fed crickets, dubia roaches, and fruit flies provides adequate nutrition without dusting. Supplementation is more relevant to reptiles than arachnids.
Can jumping spiders eat other spiders? They will try. Jumping spiders are cannibalistic toward other spiders, including other jumping spiders. Always house spiders individually. See the are jumping spiders good pets guide for more on their social behavior.
Are dubia roaches safe for jumping spiders? Yes, and they are among the best feeders available. Soft-bodied, nutritious, cannot climb smooth enclosure walls, and easy to maintain. Size nymphs to half the spider’s body length as you would with any other feeder.
What do jumping spider spiderlings eat? Spiderlings (instar 3-4) eat Drosophila melanogaster fruit flies, sized at 1-2 mm. Offer 3-5 flies every 1-2 days. As they grow into the juvenile stage, graduate to D. hydei and micro crickets. See the feeding spiderlings guide for more detail on early life stage nutrition.
Feeding questions or something unusual going on with your spider? For health concerns, consult an exotic vet who sees invertebrates. For illness signs that go beyond feeding, check our sick jumping spider guide.