What is the Diameter of a Basketball Rim – Why It’s 18 Inches

What is the Diameter of a Basketball Rim? In basketball game, two teams compete with each other, the aim of both teams is to score more goals, and it is only possible when you know about every single inch of the basketball System. That’s why, it should be better for you to know about the diameter of basketball rim.

The diameter of the Basketball Rim (Hoop/Basket) is 18 Inches which is equal to 46cm. 18 Inches diameter of basketball rim is a universally accepted measurement, whereas the diameter of the rim in FIBA is slightly different compared to other leagues. 

As the saying goes, every inch matters in the game’s measurements. So, when we talk about the diameter of the rim in basketball system then, every single centimeter matters. 

Knowing the perfect diameter of the rim is really essential because every professional player was once a beginner player.

Lebron James, Michael Jordan, Kareem Abdul-Jabbar, and more have only succeeded because of their hard work and practice because no one can get success without hard work.  

This article will explain every single piece of information about the basketball rim and its measurements in detail. So, stay tuned with us if you want to get knowledge about it.

However, if you want to know how tall a normal basketball hoop is, click on the link to get further information.

Let’s dive into the detailed review. 

What is the Diameter of Rim in Different Leagues?

Diameter of a Basketball Rim

There are four different popular leagues of basketball. So, here we will discuss the diameter of rim used in these leagues.

Diameter of Rim in NBA

NBA is the abbreviation for National Basketball AssociationThis is the league of skillful players in North America and is based on 30 teams.

The rim used in NBA has 18 inches in diameter, which is approximately equal to 46cm, and the height of the rim from the ground is 10 feet (305cm). Furthermore, the Arena Pro Goal 180 rim used in NBA which is made by Spalding. 

Diameter of Rim in NCAA

NCAA stands for National Collegiate Athletic AssociationIn NCAA, the diameter of the rim is the same as the diameter of NBA, which is about 18 inches. The rim is attach at the height of ten feet in NCAA league, if we measure it from the ground. 

Moreover, the width of the backboard used in NCAA is about 72 inches, and its height is forty-two inches; this dimension of the backboard is also same in NBA. 

Diameter of Rim in FIBA 

Actually, FIBA is derived from the French word Fédération Internationale de Basketball Amateur. It is an international basketball federation that governs the sport of basketball all over the world. The diameter of the FIBA rim is a bit different as compared to the diameter of rim use in NBA and NCAA.

FIBA has announced the authorized rule that, the minimum diameter of the rim should be 450mm, and the maximum inner diameter of the rim is about 459mm. If we talk about these measurements in inches then, it is equal to 17.70 inches to 18.0709 inches.

However, the height of the rim from the ground is the same as the height of NBA and FIBA, which is 10 Feet. 

Diameter of Rim in High Schools

Junior High Schools, WNBA, Colleges, Universities also follow the rules and regulations of the NBA and NCAA. The diameter of the rim is 18 inches, and the rim is also precisely 10 Feet above the ground.

Types of Basketball Rim 

Typically, there are two common types of rim which are mostly use in Portable basketball hoops and In-ground basketball hoops.

Classic rim

The classic rim is also known as the standard rim. We mostly see this type of rim in portable basketball hoops. This rim is directly bolted into the backboard and has no spring in it.

When there is no spring in the rim then, it means that there will be no flexibility, which is the common cause of players’ injury. 

When the classic rim is install in this basketball hoop, and the player goes for a dunk, then, as a result, it may crack or damage the backboard and may cause serious injury to the player. 

Breakaway Rim 

The high-quality breakaway rim is mostly used in NBA, FIBA, and NCAA leagues. Some of the breakaway rims come with a spring cover, which helps to keep the spring of the basketball hoop rust-resistant. 

There are one or two compressional springs attached in the breakaway rim, which may be vertical or horizontal. When the player goes for a dunk or layup shot, these compressional springs flexes under pressure. 

This rim is expensive as compared to the standard rim, but the breakaway rim allows you to play different shots like dunk shots, layup shots, bank shots, etc.…

Universally Accepted Diameter of Basketball Rim

The basketball game is getting popular game day by day, and it is one of the famous games all around the world. There are approximately 2.2 billion fan followers of basketball. 

If we talk about the USA, you won’t find a house without a basketball fan, and now the craze of basketball is spreading all over the world. 

In the most popular leagues of basketball NBA, NCAA, WNBA, High Schools, the diameter of the rim is same, but the diameter of the rim in FIBA is slightly different from these leagues. 

However, universally accepted diameter of basketball rim is 18 inches which is approximately equal to 46 inches. 

Frequently Asked Questions (FAQs)

Q1. Does all basketball rim have the same size?

Answer. Relatively all basketball rim has the same size in popular leagues like NBA, WNBA, NCAA. But, if you buy the basketball hoop for your homes, such as a portable basketball hoop or in-ground basketball hoop then, you can buy any size of a basketball rim.

Q2. How tall is a normal basketball hoop?

Answer. If you like to know about the tallness of the basketball hoop then, you can visit our complete article regarding this topic by clicking here.

Q3. How many fans followers of basketball?

Answer. The followers of basketball are rising like the speed of rocket 🚀. There are approximately 2.2 billion lovers of basketball games all over the world, and it is the third most-watched game worldwide. 

Q4. Who Invented Basketball?

Answer. James Naismith invented basketball in 1891 at the International Young Men’s Christian Association Training School. Naismith was 31-year-old when he invented this fantastic sport. And now, you won’t find, especially in the USA, a house without a basketball lover. If you want to know more about the life of James Smith then Click Here.

Q5. How to replace the basketball net?

Answer. Replacing the net of basketball always seems complicated, but we make it easy for you by writing a detailed article on this topic. So, if you want to change the basketball net, which is getting too old then, click here. 


The diameter of the rim is 18 inches in all leagues except FIBA. But the height of the rim from the ground in NBA, NCAA, WNBA, FIBA and High Schools is 10 feet. 

Thanks for staying with us till end. We are sure that this article will help you a lot while playing basketball

If you still have any queries regarding this topic, then you can ask us on the contact us page. 

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