How Long Do King Snakes Get? (And How Long It Takes To Grow)

King snakes are a manageable size that makes them ideal pets, but exactly how big they get depends on the species. If you are considering bringing a king snake home, knowing their adult size will help you plan the right enclosure and set realistic expectations.

Average Size by Species

The king snake family includes several species, and their sizes vary quite a bit. Here is what you can expect from the most commonly kept species.

California King Snakes are the most popular pet king snake and typically reach 3 to 4 feet in length as adults. Some individuals may reach up to 5 feet, but this is less common. They have a moderate body thickness that makes them comfortable to handle.

Eastern King Snakes are slightly larger, usually reaching 3 to 5 feet. They tend to be a bit heavier bodied than California kings, giving them a more substantial feel when you hold them.

Mexican Black King Snakes average 3 to 4 feet and are known for their gorgeous solid black coloring. They are similar in size to California kings and have become increasingly popular in the pet trade.

Florida King Snakes can be among the largest in the genus, sometimes reaching 4 to 6 feet. They are robust snakes with bold chain link patterns.

Gray Banded King Snakes are on the smaller end, typically staying between 2.5 and 3.5 feet. Their smaller size and beautiful banding make them popular with keepers who prefer a more compact snake.

How Fast Do King Snakes Grow

King snakes hatch at about 8 to 12 inches long, regardless of species. They grow rapidly during their first year, often doubling in length. Most of their growth happens in the first two to three years of life.

A California king snake, for example, might reach about 2 feet by the end of its first year, 3 feet by the end of its second year, and reach its full adult length of 3 to 4 feet by the time it is 3 to 4 years old. Growth rate depends heavily on feeding frequency and the size of prey offered.

Snakes that are fed more frequently and given appropriately sized meals will grow faster than those on a more conservative feeding schedule. However, overfeeding can lead to obesity, which shortens a snake’s lifespan and causes health problems. A healthy growth rate is a steady, moderate one.

Factors That Affect Size

Several factors influence how large your king snake will get. Genetics play the biggest role since the snake’s parents largely determine its growth potential. If you buy from a breeder, ask about the size of the parents to get a rough idea of what to expect.

Diet and nutrition also matter. A well fed snake with access to appropriately sized prey will reach its full genetic potential. An underfed snake may remain smaller than average.

Sex can also make a difference in some species. Female king snakes are sometimes slightly larger than males, though this varies and the difference is usually not dramatic.

Enclosure Size for King Snakes

For most adult king snakes in the 3 to 4 foot range, a 40 gallon enclosure (36 inches long by 18 inches wide) is a good minimum size. Larger species or individuals may benefit from a bigger enclosure. The general rule is that the enclosure should be at least as long as the snake, though bigger is always better.

Baby and juvenile king snakes actually do better in smaller enclosures because too much space can make them feel exposed and stressed. A 10 to 20 gallon tank works well for young snakes, and you can upgrade as they grow. To learn more about keeping king snakes, check out our guide on whether king snakes make good pets.