Size & Growth Potential of Red Eared Sliders [Size Matters]

The information is current and up-to-date in accordance with the latest veterinarian research.

So are you wondering about how big a Red Eared Slider can get in his lifetime? Well, your thinking is valid. Before going for a longer commitment to having a long-lived and messy pet like Red Eared Slider, it is better to know everything about it. Even having an idea about Red Eared Slider’s maximum size can help you to decide how you should make its habitat.

A full-grown Red Eared Slider’s size can be between 7 to 12 inches in length and the weight can be between 3 to 6 pounds. However, if they will reach their total growth potential depends a lot on some factors.

If a Red Eared Slider is given a perfect environment and foods, it is more likely for it to reach the full potential of growth within quite a less time.

How Big Do Red Eared Sliders Get? (Wild vs Captivity)

A fully grown adult Red Eared Slider can be anywhere from 7 to 12 inches. The growth rate of turtles including Red Eared Sliders depends vastly on their living conditions.

So, a Red Eared Slider living in the wild may grow bigger or even much smaller than a Red Eared Slider living in captivity. A healthy Red Eared Slider usually reaches the adult stage at the age of 8. And it is usually during this stage they reach the 7 to 12 inches benchmark in growth.

Red Eared Sliders, whether in the wild or captivity possess the same biological form. Their average growth is quite similar as well. However, as stated in the beginning, a Red Eared Slider living in the wild will grow differently from your beloved pet.

Common growth factors like UVB or basking, getting enough nutrition, etc. matters the most when determining the growth difference between Red Eared Sliders in the wild and captivity.

An adult Red Eared Slider living in the wild can grow up to 8 to 12 inches. Female Red Eared Sliders in the wild usually grow up to 10 to 12 inches while males can grow up to 8 to 10 inches.

An adult Red Eared Slider living in captivity may grow up to 7 to 12 inches depending on the environmental, nutritional, and psychological conditions. It is quite hard to calculate or predict the exact growth of each Red Eared turtle.

However, with proper care, an adult Red Eared Slider will live up to 30 years and have the potential to reach its full growth. As mentioned before, female Red Eared Sliders also grow bigger than male Red Eared Sliders. A female Red Eared Slider can grow up to 10 to 12 inches in its adult stage. A male Red Eared Slider grows up to 7 to 9 inches in its adult stage.

There are also instances where an adult Red Eared Slider has grown more than 12 inches.

6 Factors Influencing Red Eared Slider’s Growth:

The growth rate of the Red Eared Sliders is not the same for all. It varies with so many factors. Those factors play a very crucial role in determining the growth potential your Red Eared Slider would reach in his lifetime.

So let’s dive into knowing how these factors influence growth of a Red Eared Slider:

1. Balanced Diet Is Key To Turtle’s Maximum Growth

Diet is a very important factor when it comes to the growth of a Red Eared Slider. Red Eared Sliders are omnivorous when it comes to diet. This means they can eat meat and veggies both as their diet. The diet of a Red Eared Slider includes Meat, different sorts of worms, crickets, fish, vegetables, fruits, insects, and so many other things.

All the fruits and vegetables come with so many vitamins, minerals, and other stuff. But these things hardly contribute to their growth directly in any way. But the meats come with a lot of proteins and other stuff that can ensure the rapid growth of the Red Eared Slider. It is very noticeable that during the hatchling stage the Red Eared Sliders prefer to eat meaty foods mostly. This is the time they grow really fast.

Make sure you are not serving too much meat to your Red Eared Sliders as well. Try to maintain a perfect balance in the diet chart. Bring variations in the food from time to time so that the Red Eared Slider doesn’t lose its appetite.

If you are having a hard time choosing a proper diet plan for your Red Eared Slider, you can always have a consultation with a veterinarian. He will surely help you out regarding this.

2. Age vs Growth Rate

All Red Eared Sliders are born from the egg. These eggs are very tiny in size. So hatchlings are also very tiny in size. But during this stage just like the human baby, they grow really very fast. This rapid growth rate will continue for 2-4 years. After that, naturally, it will start to slow down a bit.

During the first years of life, turtles tend to grow 2-3 inches within a very short period of time. As they grow older it takes almost 14-20 months to grow an inch.

However, the scenario is completely different for the Red Eared Sliders in the wild. In that atmosphere, the Red Eared Slider tends to grow even when it is older. In fact, in the wild, the older a turtle is, the more possibility there is of it to grow even more.

The reason behind it is, when a Red Eared Slider is full-grown in the wild, then it is less likely for it to become prey for other animals. It doesn’t have to be careful during movement around other animals. It can eat and sleep without many risks around. It gets comfortable in its territory and what it has. Such comfort helps to grow even at a matured stage.

Here is how you can determine the age of a red eared slider.

3. Female Red Eared Sliders Are Bigger

The gender of the turtle is also an important determinant for determining the growth potential. Generally, the female Red Eared Sliders have a bigger size comparing to the male ones. At the young stage, it is quite difficult to identify. But as time goes by it becomes prevalent and you can clearly identify that. Here’s how you can determine the gender of a red eared slider.

A female Red Eared Slider takes more place comparing to the male Red Eared Sliders. They need to keep the eggs inside them. Probably this is the reason for their getting big so much during this time. So I guess this is why biologically female Red Eared Turtles are a little bigger than the male ones.

4. Proper UVB Lighting System Is Essential For Turtle’s Maximum Growth

It is a common practice to use UVB light in the tank. It is the most convenient light for the Red Eared Turtles living in the tank. This UVB light has a vital role in the growth of a reptile living in an artificial environment and Red Eared Sliders are no different. Red Eared Sliders need to bask in the sun so that they can get exposed to having some vitamin D. UVB light does the same for them. It is essential to retain calcium in the body.

Without having this UVB light, the Red Eared Sliders will fail to produce calcium in their body. It will drastically hamper bone and shell growth of your Red Eared Slider.

Setting up a basking area for the Red Eared Sliders like the natural habitat can contribute significantly to their growth. It lets the turtle have the required vitamin D it needs for having enough calcium in the body. It is a must to have in the tank for the Red Eared Sliders. Here is the lighting guide I wrote for red eared sliders. Read it carefully to know everything about turtle tank lighting.

Turtles not having those UVB light or the perfect setup tend to have much slower growth than the usual.

5. Proper Habitat With Enough Space Encourages Growth

A perfect sized tank and enough water are needed to create a good habitat for a turtle. If a Red Eared Slider gets an ideal habitat for him with a well-built basking spot, then it will be able to reach its full potential of growth. Be sure to provide the best filter you can as it will ultimately control the total hygiene of your turtle tank. This is the filter I’ve always use and recommended to my readers.

So you should make sure that you make a proper habitat for your turtles. This is how your turtle will be able to grow at a natural pace.

6. Captive Red Eared Sliders Can Grow More Than Wild Ones

Pet turtles are more likely to have more growth rates than wild turtles. It is because pet Red Eared Sliders get more care regarding all their necessities than the wild Red Eared Sliders. Often wild Red Eared Sliders fail to find foods for them or a suitable place to stay safe.

The pet Red Eared Sliders get it all without much difficulty. So they have more growth potential than the wild ones.

However, in the matured age, the growth rate of the Red Eared Slider living in the wild is more than those, which are living in the tank. It is due to the fact that they get more settled and have more coping mechanisms against the odds to live where they were living for the ages.

Pet Turtle Lifespan & Size Chart

pet turtle lifespan and size

If you want to get a printable version of this amazing chart, click here!

Red Eared Slider’s Growth Rate:

I have a Red Eared Slider pet for almost 5 years. From the very beginning, I was very conscious of its growth rate and all. I wanted to make sure that I hadn’t left any stone unturned regarding the proper care of my Red Eared Slider. So, I journalized all major and little stuff about my turtle along the way.

Here I will tell what I have come across till now. This will be totally based on my personal experience regarding my Red Eared Turtle.

So when I brought my Red Eared Turtle home as a hatchling it was only 2-2.5 inches long. It was so adorable with this tiny size that I almost fell in love with it looking at it at the pet store. Instantly I decided to bring it home as my pet.

After a few days, I realized my Red Eared slider was growing too fast. I decided to examine the growth of it in a proper manner. This is the stage they are prone to grow fast. So I saw it grew 2.5 to 3 inches more during the first year of bringing it home. I was pretty happy with the growth and continued giving it the same diet, environment and all.

As it grew older, I realized the growth rate narrowed somehow, comparing with the earlier days. I didn’t know that it happens naturally back then. So, I was a little bit tensed. But after having proper research, I understood the fact that with age, the growth rate of pet Red Eared Slider also decreases.

After the first year of life, the pet Red Eared Slider grew about an inch every year. This is what I found out after observing my Red Eared Slider very crucially.

Some differences of growth nature can be found between the pet Red Eared Slider and the wild Red Eared Sliders. This thing happens because of the difference in the habitat they are living in for a long time.

Red Eared Slider Size by Age Chart:

As I have told you before I have a Red Eared Slider. I have closely observed everything related to it. In this segment, I would like to help you to get some idea about the expected growth potential of Red Eared Turtles at different ages.

Remember there are so many variables associated with it. So this is not the absolute growth that your Red Eared Turtle might have. But clearly, this table can help you to get some clear idea regarding it and what to expect at a certain age.

Since I was always in touch with a reptile veterinarian regarding the well-being of my turtle and always maintained a proper diet plan, ensured a proper environment, basking area, and everything, let’s assume ensuring all these how a Red Eared Turtle is expected to grow in the different stages:

Hatchling stage 1-3 months1.5-2 inches long
1 year5 inches long (approx.)
2 year6 inches long (approx.)
3 year7 inches long (approx.)
4 year8 inches long (approx.)
5 year9 inches long (approx.)
6 year10 inches long (approx.)
7 year11 inches long (approx.)

My Red Eared Slider is 8.5 inches long now and the age is almost 5.5 years. I need to wait some more time to know what will be the growth rate practically in the coming years. So after having a proper consultation with the veterinarian and those who already have the experience of having a Red Eared Turtle for a long time I have had some ideas regarding it.

A pet Red Eared Slider can be as long as 12 inches at most. So, the weight of full-grown Red Eared Sliders stays between mostly 3-6 pounds. If they get the proper care they can live up to almost 30 years or more.

Baby Red Eared Slider Size

Baby Red Eared Sliders are quite tiny in size. They are a popular choice among many due to their incredibly small size and cute appearance. During the first three months of their life, baby Red Eared Sliders are usually 1 to 2 inches long only.

During the hatchling period, a Red Eared Slider weighs around 60 grams. Although they are incredibly small as babies, they do grow quite a bit in the next few years.

Juvenile Red Eared Slider Size

Juvenile Red Eared Sliders are usually quite bigger than their hatchling size. Many often feel surprised at their growth rate. Usually, from the age of 1 to age 4 is considered the juvenile stage for Red Eared Sliders.

At the age of one, a Red Eared Slider is usually 5 inches long. By the fourth year, your Red Eared Slider will probably grow up to 8 inches long.

Adult Red Eared Slider Size

Generally, a Red Eared Slider is considered an adult at the age of 8. However, many consider them adults at the age of 5 due to reaching sexual maturity at this age. Both male and female Red Eared Sliders reach sexual maturity at the age of 5 to 6.

At this age, a Red Eared Slider is usually 9 to 10 inches long. However, even after reaching sexual maturity, your beloved pet will grow a few more inches. At the age of 8, which is the generally considered adult stage for Red Eared Sliders, it will grow around 11 to 12 inches approximately.

Even though the growth rate of a baby Red Eared Slider is really fast, during adult years, a Red Eared Slider grows at a much slower rate. After the age of eight, the growth usually stops.

Frequently Asked Questions

How Long Does It Take For A Red Eared Slider To Fully Grow?

 It may take up to 7 or 8 years for a red-eared slider to reach its full size. The growth rate of red-eared sliders decreases as they age, but they maintain a steady rhythm until around 7 years of age when they reach their maximum size.

How Long Do Red Eared Sliders Live?

Red Eared Sliders have a longer life-span of almost 30 years. Sometimes they live even more if they get the proper care. So after having a mindset for a longer commitment like this, you should decide to have a Red Eared Slider.

You can’t decide to let go of your turtle whimsically. In some places, it is not legal to leave a store-bought Red Eared Slider to leave into the wild. This can be very dangerous for the turtle and the environment as well.

Final Words:

How big a Red Eared slider can get depends on so many determinants. Those are all discussed elaborately in this article to help you out to get some ideas about it. If you want to make sure that your Red Eared Slider reaches its full growth potential, you need to have close attention to all those factors and how they affect your Red Eared Slider.

Also, crucially observe if everything that you are applying for the betterment of your Red Eared Slider is working out well for it or not. If not, try out different things that might work out for it positively.

Even after following all do’s and don’ts you might have a few confusions regarding different nurturing ways of your Red Eared Slider. In such cases don’t forget to have a consultation session with a reptile veterinarian.

About Author

Muntaseer Rahman started keeping pet turtles back in 2013. He also owns the largest Turtle & Tortoise Facebook community in Bangladesh. These days he is mostly active on Facebook.


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