Feed prey weighing 10–15% of your ball python's body weight (ReptiFiles), no wider than the widest part of its body. Arbor View Animal Hospital's schedule: once a week up to 6 months, every 1–2 weeks at 6–12 months, every 2–3 weeks at 1–2 years and every 3–6 weeks for adults.
Estimates only. Every ball python grows at its own pace, mostly depending on how it is fed. See a reptile vet if your snake is losing weight, refusing food for a long time or looks unwell.
Ball python feeding size chart (by weight)
The simplest way to size a meal is by weight. ReptiFiles and Hudson Valley Reptile Rescue both recommend prey that weighs 10–15% of the snake's body weight, so a 40–60 g meal for a 400 g snake. Vet guides add a width check: PetMD says prey should be no wider than the snake's mid-body, and Arbor View Animal Hospital says it should be about the size of the largest part of the snake's body. This ball python feeding size chart applies the weight rule and matches each range to standard frozen feeder sizes.
| Snake weight | Prey weight (10–15%) | Matching feeders | How often | Typical stage |
|---|---|---|---|---|
| 50 g | 5–8 g | Fuzzy mouse (3–7 g), hopper mouse (7–13 g) | Once a week | Hatchling / baby |
| 100 g | 10–15 g | Hopper mouse (7–13 g), weanling mouse (13–18 g) | Once a week | Hatchling / baby |
| 200 g | 20–30 g | Adult mouse (18–30 g), jumbo mouse (30–45 g), rat pup (20–30 g), weaned rat (30–45 g) | Once a week | Hatchling / baby |
| 300 g | 30–45 g | Jumbo mouse (30–45 g), weaned rat (30–45 g), small rat (45–85 g) | Once a week | Hatchling / baby |
| 500 g | 50–75 g | Small rat (45–85 g) | Every 1–2 weeks | Juvenile |
| 750 g | 75–113 g | Small rat (45–85 g), medium rat (85–175 g) | Every 2–3 weeks | Sub-adult |
| 1,000 g | 100–150 g | Medium rat (85–175 g) | Every 2–3 weeks | Sub-adult |
| 1,500 g | 150–225 g | Medium rat (85–175 g), large rat (175–275 g) | Every 3–6 weeks | Adult |
| 2,000 g | 200–300 g | Large rat (175–275 g) | Every 3–6 weeks | Adult |
| 2,500 g | 250–375 g | Large rat (175–275 g) | Every 3–6 weeks | Adult |
Feeder weights are RodentPro's published sizes (a frozen-feeder supplier; no vet source lists gram ranges for feeder names). Feeding frequency is Arbor View's schedule, using the age a snake of that weight usually is (from our ball python growth chart). If you know your snake's age, enter it in the calculator above instead.
How much to feed a ball python
One prey item of the right size per meal is the normal approach. Over a month that adds up to less than many owners expect. A 300 g juvenile fed every 1–2 weeks eats roughly 130–196 g of prey a month. A 1,500 g adult fed every 3–6 weeks eats only about 109–326 g. The calculator shows this monthly prey estimate so you can plan how many frozen feeders to buy. Remember that this is a ceiling for healthy growth, not a target to exceed. ReptiFiles says wild adult ball pythons average only about 10 meals a year.
Ball python feeding chart by age
As a ball python grows, meals get bigger and further apart. This ball python feeding chart by age follows Arbor View Animal Hospital's vet-written schedule. Typical weights come from our size chart, and prey sizes use the 10–15% rule.
| Age | Typical weight | Prey weight | Feeding schedule | Meals per month |
|---|---|---|---|---|
| Hatchling / baby (0–6 months) | 30–480 g | 3–72 g | Once a week (7 days) | 4.3 |
| Juvenile (6–12 months) | 240–800 g | 24–120 g | Every 1–2 weeks (7–14 days) | 2.2–4.3 |
| Sub-adult (1–2 years) | 500–1,800 g | 50–270 g | Every 2–3 weeks (14–21 days) | 1.4–2.2 |
| Adult (2 years +) | 800–2,500 g | 80–375 g | Every 3–6 weeks (21–42 days) | 0.7–1.4 |
Baby ball python feeding chart
Hatchlings weigh about 30–100 g on the keeper chart we use (the Animal Diversity Web gives 65–103 g). At 50 g the 10–15% rule gives 5–7.5 g, which is fuzzy mouse (3–7 g), hopper mouse (7–13 g). By 100 g that becomes 10–15 g: hopper mouse (7–13 g), weanling mouse (13–18 g). Arbor View suggests feeding babies once a week until about 6 months. Other sources go faster (PetMD's care sheet says babies every other day, VCA says smaller or younger snakes usually eat twice a week). We use Arbor View's schedule because its author specifically warns against breeder-style fast growth. Hatchlings often refuse their first meals while settling in; VetFolio notes new snakes may fast until they get used to their surroundings.
Juvenile and sub-adult feeding
Between 6 and 12 months, Arbor View moves to every 1–2 weeks, and from 1 to 2 years to every 2–3 weeks. Juveniles move from mice to small rats: at 500 g the rule gives 50–75 g, which is small rat (45–85 g). ReptiFiles notes that young adult females around 1,000 g often go off food for a while, a pattern keepers call "the Wall".
Adult ball python feeding schedule
Arbor View treats snakes over 2 years as adult size and suggests a meal every 3–6 weeks. A 1,500 g adult needs 150–225 g, which is medium rat (85–175 g), large rat (175–275 g). Arbor View explains that a ball python's metabolism is very slow: an adult takes up to 2 weeks to return to its normal metabolic state after a meal, so frequent meals aren't needed. Other guides suggest every 7–10 days for adults (VetFolio, Hudson Valley Reptile Rescue). If you feed more often than Arbor View suggests, keep meals at the low end of the size range and watch body condition closely.
How often should you feed a ball python?
This is where sources disagree most, so here is how often to feed a ball python according to each one:
| Source | Babies | Juveniles | Adults |
|---|---|---|---|
| Arbor View Animal Hospital (vet, 2021) | Once a week (to 6 months) | Every 1–2 weeks (6–12 months); every 2–3 weeks (1–2 years) | Every 3–6 weeks (over 2 years) |
| VetFolio (veterinary technician guide) | Every 5–7 days | Every 5–7 days | Every 7–10 days |
| VCA Animal Hospitals (all snakes) | About twice a week | About twice a week | Once every 1–2 weeks |
| PetMD care sheet (vet) | Every other day | Once a week | Every 1–2 weeks |
| Hudson Valley Reptile Rescue | More often than adults | Gradually less often | Every 7–10 days |
The spread reflects different goals. Faster schedules grow a snake quickly and are common among breeders; Arbor View notes that many feeding guides are geared to bringing snakes up to breeding weight as fast as possible, and that obesity is a common problem in pet ball pythons. Slower schedules keep a pet lean. Every source agrees on the trend: young snakes eat more often than adults, and the schedule should change with body condition. VCA adds a useful rule: if your snake eats readily, it was hungry; if it doesn't, it probably didn't need feeding yet.
So how often do ball pythons eat in the wild? Much less than in most homes. ReptiFiles says wild adults average about 10 meals a year, and VetFolio notes that wild ball pythons eat less or stop eating in December and January, when nights cool to the low 70s °F (about 22 °C). The calculator uses Arbor View's schedule as the default ball python feeding schedule and flags anything faster in the current-prey check.
What size rat or mouse should I feed my ball python?
Feeder rodents are sold by size names rather than grams, and the names vary a little between suppliers. This table uses RodentPro's published weight ranges. The last column shows which snake weights each size suits under the 10–15% rule, which answers both what size mouse for ball python hatchlings and what size rat for ball python adults.
| Feeder size | Weight (RodentPro) | Suits a ball python of |
|---|---|---|
| Pinky mouse | 1.5–3 g | about 10–30 g |
| Fuzzy mouse | 3–7 g | about 20–70 g |
| Hopper mouse | 7–13 g | about 47–130 g |
| Weanling mouse | 13–18 g | about 87–180 g |
| Adult mouse | 18–30 g | about 120–300 g |
| Jumbo mouse | 30–45 g | about 200–450 g |
| Rat pup | 20–30 g | about 133–300 g |
| Weaned rat | 30–45 g | about 200–450 g |
| Small rat | 45–85 g | about 300–850 g |
| Medium rat | 85–175 g | about 567–1,750 g |
| Large rat | 175–275 g | about 1,167–2,750 g |
A few practical points follow from these numbers:
- Pinkies are too small for most ball pythons. At under 3 g, a pinky mouse is under 10% of even a 30 g hatchling. Most hatchlings start on fuzzy or hopper mice.
- Mice run out early. The biggest jumbo mice weigh about 30–45 g, which only covers snakes up to about 450 g. Above that, one mouse is too small a meal, so most keepers switch to rats.
- Rats cover the adult range. A medium rat (85–175 g) suits snakes of roughly 570 g to 1.75 kg, and a large rat (175–275 g) suits about 1.2–2.75 kg.
- Variety is fine. Arbor View lists mice, rats, chicks, quail, gerbils and African soft-furred rats as acceptable, and notes that wild males eat many birds. VCA says whole prey such as mice and rats makes a balanced diet, and that pet snakes generally don't need vitamin supplements.
- Width matters as much as weight. A prey item should be no wider than the widest part of your snake (PetMD, Arbor View). If a feeder is the right weight but looks too bulky, choose the smaller size.
Frozen-thawed vs live prey
The short answer on frozen-thawed vs live for ball pythons: every source we checked recommends frozen-thawed (or freshly killed) prey. VCA's vets explain why: rodents can bite a snake before they are eaten, and "even a small bite from a mouse can cause a severe, potentially life-threatening infection". VCA adds that prey suffers stress while being hunted, and that frozen prey lowers the risk of disease and parasites. PetMD's care sheet says not to feed live prey, and Arbor View says live prey should be avoided because it can seriously injure the snake. Arbor View also notes that most snakes can be switched from live to frozen-thawed with time.
When live feeding is the only option, for example with a nervous hatchling, supervise the whole time. ReptiFiles says to remove an uneaten feeder within 15–30 minutes, VetFolio says no more than 30 minutes, and VCA's absolute limit is two hours. VetFolio notes that baby ball pythons have a timid strike response, which is why some start on live food, but the goal should always be to move them onto pre-killed prey.
How to thaw frozen prey
ReptiFiles recommends thawing the feeder in the fridge overnight. About 15–30 minutes before feeding, seal it in a plastic bag and warm it in hot water to about 98–100 °F (37–38 °C), close to a live rodent's body temperature. Never microwave a feeder, and never refreeze one that has thawed.
How to feed a ball python safely
This checklist brings together the general guidance from our sources:
- Weigh your snake first and use the calculator to pick a prey item of 10–15% of its weight that is no wider than its widest point.
- Thaw and warm the prey as described above, so it is warm right through.
- Offer it with long tongs, not your fingers, at dusk or in the evening. Ball pythons are most active at dawn and dusk (Arbor View).
- Feed inside the enclosure if your snake eats reliably there. ReptiFiles says moving a snake to a separate box often stresses it into refusing food; if you use loose substrate, a feeding dish or paper helps keep bedding off the prey.
- Leave it alone. Don't handle your snake for 24–48 hours after a meal; handling can cause regurgitation (Arbor View).
- Remove refused prey after a short wait and don't offer another until the next scheduled day (Hudson Valley Reptile Rescue).
- Keep fresh water available in a bowl large enough to soak in (Arbor View, VCA).
- Record it. Note the date, feeder size and whether it ate, and weigh your snake monthly. A feeding log makes fasts and weight changes easy to spot.
Power feeding and obesity: why more isn't better
Power feeding ball pythons means feeding them more often, or giving larger meals, than they need, usually to make them grow faster. It is common in breeding, where females must reach a certain weight before they can breed; VetFolio notes females mature at around 1,000 g. Arbor View warns that many online feeding charts come from this world, and that obesity is a common problem in ball pythons. ReptiFiles calls obesity "rampant" among pet ball pythons.
The calculator flags possible power feeding when you enter your current routine and either the prey is over 15% of body weight, or you feed more often than Arbor View's schedule for that age. For example, a 400 g juvenile fed an 80 g rat every 5 days triggers the warning on both counts (20% of body weight, and more often than every 1–2 weeks).
How to tell whether your snake is overweight:
- Its back looks rounded or flat with no visible spine (ReptiFiles).
- It shows rolls or bulges of skin when it bends (Arbor View).
- Its weight keeps rising after it has reached adult length. Our ball python size by age calculator shows whether a weight is typical for an age.
The fix is general and gradual: smaller prey, longer gaps between meals, and regular weigh-ins. Don't crash-diet a snake. If you are unsure, or your snake is very heavy, ask a reptile vet to assess its body condition.
Why is my ball python not eating? (fasting explained)
A ball python not eating is the most common worry owners have, and often it isn't a crisis. Arbor View describes ball pythons as known for going off food for months at a time; the vet guide says they are adapted to an infrequent feeding schedule, though husbandry problems are often the cause. VetFolio reports two cases of ball pythons fasting for up to 22 months. Common reasons include:
- Season and breeding: males often fast in winter, which is breeding season (Arbor View, ReptiFiles), and wild ball pythons eat less or stop in December and January (VetFolio).
- Females carrying eggs may stop eating until the eggs hatch (VetFolio).
- Shedding: snakes are less likely to eat while shedding (VetFolio, VCA).
- Stress: a new home, noise, lack of hiding places or frequent handling. VetFolio advises not handling a new snake until it has eaten at least four times in a row.
- Husbandry: wrong temperatures or humidity. Arbor View gives a basking spot of 95–100 °F, a warm side of 85–90 °F and a cool side of 75–80 °F.
- Illness: VCA lists intestinal parasites, viral infections, kidney failure and cancer among the more serious causes of a poor appetite.
Ball python fasting is usually safe as long as the snake holds its weight. Arbor View and ReptiFiles both use the same line: weigh regularly, and if your snake loses more than 10% of its body weight, see a reptile vet. See a vet sooner if a fasting snake also looks thin, regurgitates, has mouth or breathing problems or seems weak. This page gives general information only. We don't give medication or treatment advice, and you shouldn't force-feed a snake unless a vet tells you to.
Royal python feeding chart
Royal pythons and ball pythons are the same species, Python regius. Royal python is the usual UK and European name, and Arbor View's vet guide is titled "Ball/Royal Python". Every number on this page therefore works as a royal python feeding chart: the same 10–15% prey rule and the same schedule.
The main difference is vocabulary. UK suppliers may call rodent sizes by slightly different names or sell them in other gram bands, so always check the weight printed on the pack rather than the name. Use grams in the calculator; it accepts ounces and pounds too. As a metric example, a 1 kg royal python needs about 100–150 g of prey, which is medium rat (85–175 g).
How this ball python feeding calculator works
Feeders = every RodentPro size whose gram range overlaps that prey range
Interval = Arbor View schedule for the snake's age (estimated from weight if you leave age blank)
Prey per month = prey weight × 30.44 ÷ days between meals
Enter your snake's weight in grams, ounces or pounds. If you also enter its age, the feeding interval comes from Arbor View's schedule for that age. If you leave age blank, the calculator estimates age from weight using the same growth chart as our size calculator (sex unknown) and picks the matching interval. The result shows the prey weight range, matching mouse and rat sizes, the interval in days, meals per month and an estimate of prey per month. The bar shows where 10–15% sits on a 0–25% scale, with your current prey marked if you enter one.
The optional current-prey check compares your routine with the guideline. It warns about possible power feeding if the prey is over 15% of body weight or if meals are closer together than the schedule allows. If you enter an age, it also tells you when the snake is heavier than is typical for that age. The tool can't see your snake, so use it together with a body-condition check and your reptile vet's advice. If you keep a bearded dragon as well, the bearded dragon feeding schedule works the same way, and corn snake keepers can use our corn snake feeding chart.
Frequently asked questions
What is the ball python feeding size chart?
Feed prey that weighs 10–15% of your snake's weight (ReptiFiles) and is no wider than its widest point. For example: 100 g snake → 10–15 g; 500 g → 50–75 g; 1,500 g → 150–225 g.
How often should I feed my ball python?
Arbor View Animal Hospital suggests once a week up to 6 months, every 1–2 weeks at 6–12 months, every 2–3 weeks at 1–2 years and every 3–6 weeks for adults over 2 years. Other guides feed adults every 7–10 days.
How often do ball pythons eat in the wild?
Rarely. ReptiFiles says wild adults average about 10 meals a year, and VetFolio notes they eat less or stop in December and January.
What size rat should I feed my ball python?
Pick a rat that is 10–15% of your snake's weight. A 500 g snake suits a small rat (45–85 g); a 1,000 g snake medium rat (85–175 g); a 1,500 g snake medium rat (85–175 g), large rat (175–275 g).
What size mouse should I feed a ball python?
Most hatchlings (50–100 g) take fuzzy or hopper mice. A 300 g juvenile suits jumbo mouse (30–45 g), weaned rat (30–45 g), small rat (45–85 g). Mice only cover snakes up to about 450 g; bigger snakes need rats.
How much should I feed a ball python?
One prey item of 10–15% of body weight per meal. Over a month that is roughly 40–70% of body weight for a baby fed weekly, falling to around 5–20% for an adult fed every 3–6 weeks.
What is the baby ball python feeding chart?
Hatchlings of about 50–100 g need prey of about 5–15 g (fuzzy to hopper mice), once a week until about 6 months (Arbor View).
What is a good adult ball python feeding schedule?
A meal every 3–6 weeks for adults over 2 years (Arbor View), adjusted to body condition. VetFolio and Hudson Valley Reptile Rescue suggest every 7–10 days.
Is frozen-thawed or live prey better for ball pythons?
Frozen-thawed. VCA warns that even a small mouse bite can cause a severe, potentially life-threatening infection, and PetMD and Arbor View advise against live prey. Thaw in the fridge and warm to about 98–100 °F (ReptiFiles).
Why is my ball python not eating?
Often it's normal: winter and breeding-season fasts, shedding, egg-laying, a new home or too much handling. Wrong temperatures and illness can also cause it. Weigh your snake, and see a reptile vet if it loses more than 10% of its body weight (Arbor View).
How long can a ball python go without eating?
Healthy ball pythons often fast for weeks or months, and VetFolio reports two fasts of up to 22 months. What matters is weight: see a reptile vet if your snake loses more than 10% of its body weight or looks thin.
What is power feeding a ball python?
Feeding more often or bigger meals than needed to speed up growth, usually for breeding. Arbor View warns that obesity is common in ball pythons; the calculator flags prey over 15% of body weight or meals more frequent than the schedule.
Is the royal python feeding chart different?
No. Royal pythons and ball pythons are the same species, Python regius, so the same 10–15% prey rule and feeding schedule apply.
This calculator gives an estimate for education and fun. Every pet ages differently — for health decisions, talk to your veterinarian.