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Painted Turtle Size: Subspecies Size Comparison, Growth Rate, and More

Painted turtles are relatively small. The average painted turtle grows to be 4-10 inches long. Females are bigger than males, as they need extra space for reproductive purposes. The size does differ depending on their diet, habitat, and other external factors.

Do you have a painted turtle as a pet? If so, you may be wondering how big your little guy or gal will get. 

What kind of growth rate can you expect? And is there anything else you should know about the size of painted turtles?

This post compares the size and growth rate of the three subspecies of painted turtles and discusses some frequently asked questions. Knowing what to expect can help you better prepare for taking care of your new pet turtle.

Painted Turtle Size

Painted turtles generally grow to be between 4 and 10 inches. Some individuals can grow up to 12 inches. The size differs between the three distinct subspecies.

There are three different subspecies of painted turtles, and they can vary slightly in size. The biggest difference is between males and females, with females typically about 10% larger than males.[1]

Other factors that influence a painted turtle’s size include its diet, habitat, and the amount of daylight it receives. Turtles that live in areas with long periods of daylight tend to grow larger than those with shorter days. 

On average, painted turtles are relatively small.

Eastern painted turtle

Painted Turtle Subspecies Size Comparison

There are three subspecies of the painted turtle: 

There were formerly four subspecies that included the smaller southern painted turtle, but it is now considered a separate species.[2]

Subspecies Size (in inches)
Eastern painted turtle 5–7
Western painted turtle  8–10
Midland painted turtle  4–10

Factors That Influence Painted Turtles Size

Three main factors influence the growth rate and size of painted turtles: their diet, the environment, and gender.

Related: Painted Turtle: Care, Habitat, Appearance & More

Diet

Painted Turtles Temperature

What a painted turtle eats can play a role in its size. A protein- and calcium-rich diet helps promote growth. In the wild, turtles eat a variety of foods:

  • Insects
  • Fish
  • Frogs
  • Crustaceans
  • Aquatic plants.

A healthy diet for a pet painted turtle includes both animal and plant matter. Commercial turtle food works great, but earthworms, crickets, fish, and other small invertebrates are also excellent protein sources.

Environment

Western Painted Turtle Habitat And Distribution

The environment can influence the size of painted turtles. Turtles living in warm, sunny areas tend to grow larger than those in cooler, darker environments. Vitamin D, which helps the turtles absorb calcium and phosphorus, is produced in the skin when exposed to sunlight.

In addition, painted turtles living in areas with access to a large body of water tend to grow larger than those in smaller habitats. This may be because they have more room to swim and hunt for food.

As pets, painted turtles need a large, warm tank with access to UVB light. The tank should also have a basking area where the turtle can dry off and warm up.

Gender

There is a significant difference between male and female painted turtles, with females typically about 10% larger than males. This is because males have to compete for mates, so they need to be able to move quickly to escape predators and chase after females. Females need larger bodies to facilitate the production of eggs.[4]

How To Tell How Old A Painted Turtle Is

To tell how old a painted turtle is, you can compare its size to a growth chart, assess their shell coloration, or count the rings on their scutes.

Size

Western Painted Turtle Anatomy and Appearance
Image Source

The size of a painted turtle is the best indicator of its age since it grows at a more or less consistent rate throughout its life.[5] To estimate your turtle’s age, you can compare it to a growth chart shows the average size for turtles of different ages.

Shell Coloration

Additionally, the shell of an older turtle is usually darker and more worn than that of a younger turtle. This is because the shell is made of keratin which deteriorates over time.

Scute Rings

painted turtle brumation

Another way to estimate the age of a painted turtle is by counting the number of annuli, or growth rings, on its shell. These rings are formed as the turtle’s shell grows and can be used to estimate the turtle’s age. For example, a turtle with 12 annuli is three to four years old.

Painted Turtle Growth Rate

Painted turtles grow rapidly in their first year of life, reaching around three inches at one year old. They then grow around one inch per year until they reach sexual maturity.

Male painted turtles reach adulthood at around four to five years old, while females reach adulthood at around six to seven years old.

This later maturity for females allows them to grow more. This is useful to prepare them for reproduction.

Painted Turtle Size/Age Chart

Age (years) Western Eastern Midland
0–1 4 in 3 in 3 in
1–4 6 in 5 in 5 in
4–5  8 in 6 in 7 in
6–7 10–12 in 8 in 10 in

When Are Painted Turtles Fully Grown?

Painted turtles grow slowly but steadily throughout their lives. They reach their full size between four and seven years old. They stop growing at the very latest at ten years old.

How Big Do Painted Turtles Get In Captivity?

It is not uncommon for pet-painted turtles to grow to be around seven to ten inches long. Some individuals can grow larger than this.

There is the opportunity for captive painted turtles to reach larger sizes than their wild counterparts due to a steady food source and a perfect environment.

Alternatively, captive turtles may not reach their growth potential due to poor diets and environments from inexperienced owners.

Related: Painted Turtle Lifespan: Wild vs. Captivity Life Expectancy

Western Painted Turtles Size and Growth Rate
Image Source

How To Make A Painted Turtle Grow Faster

Painted turtles usually grow at a steady rate throughout their lives. In captivity, great care, a balanced diet, and an excellent environment support their growth.

Some of the things you can do to help your turtle grow faster include:

  • Providing a healthy diet rich in nutrients and calories (high-quality turtle food pellets, fresh fruits, veggies, and live prey items).
  • Create a warm and humid environment for your turtle to live in, with a basking spot with a UVB light for UV exposure.
  • Make sure your turtle has access to plenty of water for swimming and soaking.
  • Provide a clean, spacious enclosure.

Conclusion

Painted turtles are fairly small, typically growing between 5 and 10 inches in length. They grow at a relatively consistent rate throughout their lives and reach sexual maturity around 4-7 years old. 

While there can be differences in size between wild and captive painted turtles, proper care should allow your pet to reach its maximum potential size.

FAQs

How Big Do Painted Turtles Get?

Painted turtles typically grow to be between five and ten inches long, although some individuals may grow slightly larger or smaller than this.

How Big Should A Painted Turtle Tank Be?

The minimum tank size for a painted turtle should be at least ten gallons per inch of shell. A 5-inch turtle needs a minimum of 50 gallons while a 12-inch individual needs 120 gallons.

How Big Is A 1-Year-Old Painted Turtle?

A one-year-old painted turtle typically measures between three and four inches long. Painted turtles tend to grow more rapidly in their first year of life than they do during subsequent years.

How Big Is The Biggest Painted Turtle?

The size of the largest painted turtle is not well-documented. Some pet owners have reported their turtles have reached lengths of up to 12 inches. It is possible for wild individuals to grow even larger.

Do Painted Turtles Stay Small?

Painted turtles are reasonably small compared to other pet turtles. Western painted turtles can reach up to 12-inches in length, while the closely related species (the Southern Painted Turtle) only reach 5 inches.

How Big Are Painted Turtles When They Hatch?

Hatchling painted turtles are typically around 1-2 inches in length.

About Sophie Herlihy (Zoologist)

Sophie Herlihy, a trained zoologist, is a lover of true misfit animals. With a specialty in insects, birds, and rodents, she helps the Misfit Animals craft factual and valuable informational pieces on various animals.