Ball Python Size & Weight Chart by Age
Last updated: · Reviewed against sources listed below
This ball python growth chart shows typical weight and length by age. Hatchlings weigh 60–100 grams, and most ball pythons reach 1,000–2,500 grams and 3–5 feet as adults. Females usually grow larger than males.
Estimate
- Estimated age
- Normal range for that age
- Compared with normal
This is our reptile age and growth estimator, preset for ball pythons.
Ball Python growth chart by age
Weight is the most useful measure for snakes. Growth varies a lot with feeding and genetics, so treat these as broad ranges. Use the °F / in button at the top of the page to switch to centimeters.
| Age | Total length | Weight |
|---|---|---|
| Hatchling | 10–17 in25–43 cm | 60–100 g (2.1–3.5 oz)60–100 g |
| 3 months | 14–20 in36–51 cm | 100–200 g (3.5–7.1 oz)100–200 g |
| 6 months | 18–24 in46–61 cm | 200–400 g (7–14 oz)200–400 g |
| 9 months | 20–28 in51–71 cm | 300–600 g (11–21 oz)300–600 g |
| 12 months | 24–32 in61–81 cm | 400–800 g (14–28 oz)400–800 g |
| 18 months | 2.3–3 ft71–91 cm | 600–1100 g (21–39 oz)600–1100 g |
| 2 years | 2.5–3.3 ft76–102 cm | 800–1500 g (28–53 oz)800–1500 g |
| 3 years | 3–4.5 ft91–137 cm | 1000–2500 g (35–88 oz)1000–2500 g |
How big do ball pythons get?
Adult ball pythons usually measure 3–5 ft91–152 cm and weigh 1000–2500 g (35–88 oz)1000–2500 g. Males are typically at the smaller end, around 2–3 feet and 1,000–1,600 g. Females are usually longer and heavier, often 3–5 feet and 1,500–2,500 g. Very large individuals exist, but a ball python over about 6 feet is rare.
Ball pythons grow fastest in their first two years and reach adult size around 3 years for males and 3–5 years for females.
Tracking your ball python’s weight
Weigh your snake in grams every two to four weeks, before a meal. Put it in a lidded tub or pillowcase on a digital kitchen scale and subtract the container weight. Keep a log alongside feedings; the feeding calculator can print one for you.
Body shape matters as well as weight. A healthy ball python has a rounded, loaf-like cross-section. A visible spine ridge suggests the snake is underweight, while fat rolls when it bends or a wide, flat body suggest it is overweight.
Why is my ball python growing slowly?
- Normal feeding breaks. Many ball pythons pause eating for weeks, especially in winter.
- Low temperatures. A basking area below about 88°F31°C slows digestion.
- Prey too small or too infrequent for the snake’s weight.
- Stress from too much handling, open enclosures or a busy room.
- Parasites or illness. A vet check and fecal test can rule these out.
If your ball python is losing weight rather than just growing slowly, or shows respiratory signs such as wheezing or mucus, see a reptile vet.
Frequently asked questions
How fast do ball pythons grow?
Most ball pythons grow from about 60–100 g at hatching to 400–800 g by their first birthday, and reach 800–1,500 g by age two. Growth then slows. Feeding frequency, temperature and genetics all affect the rate, so two healthy snakes of the same age can differ a lot.
How do I know if my ball python is underweight?
Look at the body shape as well as the scale. An underweight ball python has a visible ridge along its spine and a triangular cross-section, and its skin may look loose. Compare its weight with the chart for its age. If it is thin and not eating, or losing weight, a reptile vet should check it for parasites and infection.
At what age is a ball python fully grown?
Males are usually fully grown around 3 years old. Females keep growing longer and are often full size between 3 and 5 years. After that, weight changes mostly reflect feeding and body condition. Keep weighing your snake every few weeks as an adult to catch any weight loss early.
Sources
- VCA Animal Hospitals — Snakes: Owning
- Wikipedia — Ball python
- ReptiFiles — Ball Python Care Guide
- Merck Veterinary Manual — Reptiles (Pet Owner Version)
Where sources disagree we show the range they share. See our sources and methodology for how every number is checked.