How Big Do Red Eared Slider Turtles Get? Average Size & Growth Chart

Red eared sliders are one of the most popular turtles kept as pets, especially in the realm of aquatic turtles. These cute turtles are often purchased when very small, and unfortunately, it’s not uncommon for them to end up in homes that are ill-prepared for their care and long-term needs.

Before bringing one of these turtles home, it’s important to fully understand what you’re getting into, including how large you can expect your turtle to get, since this will impact the size of enclosure you need, as well as the water filtration and food needed.  A fully grown red eared slider turtle can grow to be  5–11 inches long. Let’s talk about how big red eared slider turtles get.

Red-Eared Slider Turtle Breed Overview

Red eared sliders are native turtles in the US, and they are the most common aquatic turtle species in most US states. These turtles should never be taken from the wild, though, and in many places, they are protected. They can be purchased from breeders, however.

These turtles are named for the red stripe behind their eye, and the “slider” part of their name refers to their tendency to slide from rocks, logs, and other basking spots when they feel threatened or startled.

They can live for decades, with some turtles living to their 30s, so the red eared slider is not a short-term commitment. They do make good pets, though, and tend to be curious and interactive with their people, especially during mealtimes.

Red Eared Slider Turtle Size and Growth Chart

You may find red eared sliders in a variety of color morphs, but they all belong to the same species of turtle. Here’s what you can expect from the growth of your turtle. It is not legal for red eared sliders to be sold when they are smaller than 5 inches in length, so you can expect any red eared slider you purchase to already be an adult or an older juvenile.

When Does a Red Eared Slider Turtle Stop Growing?

Red eared sliders will grow until they are around 5 years of age, which is when they are considered to have reached adulthood. They will have little to no growth left after 5 years, although their weight may shift with age. Females tend to be larger than males, so you can expect a faster growth rate with a female than a male, although these turtles in general grow quickly, which keeps them safe in the wild.

Factors Affecting the Size of Red Eared Slider Turtles

Multiple factors can affect the size of your red eared slider. Providing them with appropriate nutrition is necessary to maintain healthy growth, as well as meeting their needs with excellent water quality and UVB lighting. Poor water quality, lack of access to UVB lighting, and inappropriate temperatures can all impact the growth rate and adult size of your turtle. Other factors influencing size include genetics, health, and sex.

Ideal Diet for Maintaining a Healthy Weight

It’s generally recommended to feed your red eared slider a commercial turtle food in order to ensure their nutritional needs are being met, and then offer occasional treats. However, there are many foods that can be offered to red eared sliders: leafy greens, crickets, earthworms and nightcrawlers, superworms, and freeze-dried krill or shrimp. In the wild, they eat aquatic plants, insect larvae, worms, aquatic insects, small crustaceans, small fish, and decaying matter, including dead plants and animals.

How to Measure Your Red Eared Slider Turtle

The easiest way to measure your red eared slider’s body length is to use a soft tape measure. You’ll only measure the length from end to end of the carapace, not counting the head, neck, or tail as part of the length. For weight measurements, a small scale is appropriate, including food and baby scales. You may need a bowl or cup that can contain your turtle to keep them still during weighing, but make sure to account for the weight of the cup in your measurements.

Always wash your hands thoroughly before and after handling your turtle and anything in their enclosure. Turtles can carry bacteria and diseases that can be spread to humans, and you can also put your turtle in danger if your hands have cleaning products, lotions and soaps, and cosmetics on them. Whenever possible, aim to use disposable gloves when handling your turtle. Always properly disinfect surfaces that your turtle touches outside their enclosure.

Conclusion

Red eared sliders make excellent pets, but once they reach their full adult size, they need a tank that is at least 100 gallons. They also need space outside of the water to bask. Make sure you’re fully prepared to provide an appropriate enclosure before bringing a red eared slider home.

These turtles grow quickly, reaching their full adult size by around 5 years of age, even though they can live to around 30 years. You can expect at least an inch of growth per year in the first few years of life for a red eared slider, but you will likely purchase an adult turtle because of the laws and restrictions regarding the sale of small turtles. Because of this, your turtle’s enclosure should be set up for a fully adult-sized turtle. While some animals can start off in a smaller enclosure, only needing a larger space later on, you will likely have a full-grown or almost full-grown turtle.

---

Featured Image Credit: Simon_g, Shutterstock