Every ball python owner wants to know if their ball python is growing and developing properly, and gaining weight as it should. In this post, you will find a ball python growth chart and weight chart, ball python growth stages and rates, average weight by age, how to tell if your ball python is overweight or underweight and more.
Ball pythons grow at different rates – it will depend on how often you feed your ball python, its genetics and husbandry. Appetite will also depend on ball python’s current well-being.
Please note that weights and sizes provided in the charts below are only an average and vary greatly. There are different factors that will affect your ball python’s development. If you are worried about your ball python being underweight or overweight, please see a vet.
Please allow your ball python to develop at its own rate and don’t force or power feed to make it grow faster. That is unhealthy and stressful for your ball python. The best way to tell if your ball python is a healthy weight is to assess it visually (you will find how below).
Ball python weight chart
| Age of a ball python | Weight of a ball python |
| Hatchling, 0-4 weeks | 45-105 grams (45-70 grams in an average) |
| 1 month old | 60-105 grams |
| 2 months old | 80-130 grams |
| 3 months old | 130-200 grams |
| 4 months old | 200-270 grams |
| 5 months old | 270-300 grams |
| 6 months old | 300-360 grams |
| 7 months old | 360-400 grams |
| 8 months old | 400-450 grams |
| 9 months old | 450-470 grams |
| 10 months old | 470-500 grams |
| 11 months old | 500-700 grams |
| 12-18 months old | 500-1,000 grams (600-750 grams on average, but for males, as low as 400 grams) |
| 18-24 months | 600-1,800 grams |
| 24 months old | 800-1,800 grams |
| 30 months old | 1,120-1,800 grams |
| Adult (3 years old and over) | 1,200-1,800 grams, up to 1,800-2,300 grams, can reach even 3 kg. Females will be larger. Smaller specimens might only weigh 800-1,000 grams |
Please note, that there is no set ball python growth chart that will show you ideal ball python weights. Ball pythons grow at very different rates, and a lot is also affected by other internal and external factors. Genetics also play a big role in development.
To consider how fast your ball python is growing, take into an account its hatch weight, which feeders it’s being offered (ball pythons on rats will gain more). Also, consider how often it’s being fed, prey size, general health condition.
Make sure to monitor your ball python’s weight since you get it. It’s a great idea to get a journal and digital kitchen scales like this. Write down your ball python’s weight once in 2-4 weeks to see growth rate.
If your new ball python is underweight, you can feed it more often/offer larger prey (within limits). But please never power feed or overfeed. This can only cause regurgitation and will make your ball python go on hunger strikes.
You can find ball python weight and feeding sizes chart in this post (new tab).
Ball python length by age
Same as with weight ratios, there is no set length that your ball python should be at certain age. It will differ in ball pythons and will be affected by both internal and external factors.
In general, ball python hatchlings are around 8-18 inches (20-46 cm). By 2-6 months of age, ball pythons reach 16-27 inches (40.6-67cm). From 6-15 months old, a ball python can range between 20-40 inches (51-102 cm), but this can differ as well.
Adult ball pythons of over 3 years of age can reach 3-5 feet (91-152 cm). Females will be generally larger than males. Smaller males might reach only 2-2.5 feet (61-76 cm) long.
Ball python guide on weight
Ball python’s weight will depend on many factors. Let’s discuss each factors and see numbers and examples.
#1: Female ball pythons get larger and heavier than males.
#2: One of them is what you feed your ball python. For example, if you switch to feeding rats earlier, your ball python is going to gain weight more quickly. It is a good idea to switch to rats as soon as your ball python hits 150-200 grams or similar.
#3: Larger ball pythons generally weigh more. Body construction is important when looking at ball python’s weight. This start being more noticeable as your ball python grows, after around 1-2 years of age. A ball python that is 4-5 feet will often reach around 2-2.5 kg.
#4: Not all ball pythons should weight the same. Some ball pythons with lower weight will appear firmer and plumper than those that are heavier.
How to tell if a ball python is a healthy weight?
A ball python that’s a healthy weight will have a healthy physique – a lean triangular shape body. There should be no fat deposits or rolls all throughout the body, giving your ball python a full round look.
Your ball python’s spine must be somehow prominent, rather than sunken (sings of obesity). Also, your ball python’s head must not look much larger compared to its body.
How to tell if ball python is overweight?
Visual assessment of your ball python is of the most reliable ways to tell if your ball python is overweight.
#1: Look at your ball python’s body, especially around belly and neck. Are there any rolls when it’s curled up? Are there any skin folds? Fold and rolls will indicate excess weight.
#2: Your ball python should show symmetry from neck to body. If your ball python is too round, it could be overweight. Normal weight ball python should have a triangular shape.
#3: Does your ball python feel firm when you handle it? If it feels too soft, it might be overweight or generally have extra weight.
#4: If you can feel extra fat under your ball python’s skin, it could be overweight.
#5: If your ball python’s head looks much smaller than its body, then it is overweight or even obese. Ball python’s head must not look much smaller than its body girth (body girth should be around 3 times larger than the head).
#6: Your ball python is overweight or obese if you can see accumulation of fat before the vent/cloaca area. Healthy weight ball python must gradual tapering down of fat deposits from the mid-top and up to the tip of the tail.
#7: You will barely see your ball python’s spine, or won’t be able to see it at all if it’s overweight or obese. It will look sunken.
Is my ball python underweight?
#1: Concave/depressed belly and even loose skin can indicate that your ball python is underweight. Dehydration can also lead to this, however.
#2: Sharp and sticking out spine.
#3: Larger head when compared to the body.
#4: Thin and wrinkly neck.
How to make an overweight ball python lose weight?
If your ball python is overweight or obese, you might need to review its diet and cage decorations. Feeding frequency and prey size are the main factors that will determine your ball python’s weight.
Do not power feed to make your ball python grow faster. Feeding ball pythons over 12 months of age once in 2 weeks is enough. You can find a feeding chart for ball python age and weight here.
What is more, take your ball python out when possible to encourage it to roam, burn calories and build muscle. Make sure your ball python’s cage is not too small (see ideal cage sizes here) and include cage decorations for some climbing.
How to make an underweight ball python gain weight?
If your ball python is underweight, you can slowly get it to normal weight. Please note, it must be gradual. You should never feed too much, too often, or big prey items to make it put on weight quickly.
This will make your ball python sick, will cause regurgitation and make it go on hunger strikes. If your ball python is too sick and underweight, please see a vet.
Internal parasites must be ruled out with new ball pythons (especially wild-caught). In more serious cases, assisted feeding or even force feeding (last resort) might be needed.
Thank you for reading this ball python growth and weight chart! You can find a diet guide for your ball python here. For more ball python care guides and posts, visit this resource page.