Are you searching for information about the tips and tricks that can help you calculate the diameter of a circle? This is a common problem that learners used to face while learning geometry. However, diameter is the longest chord of a circle that passes through the Centre to meet with a circumference at opposite ends. So if you are wondering **how to find the diameter of a circle**, it is twice the length of the radius.

But, if you don’t know about the radius and other dimensions, you should not worry. This article is for those learners who are at an entry-level stage in the world of geometrical figures. Here, you will learn a piece of comprehensive information about what is diameter, radius, and circumference. Additionally, it will offer you valuable insights on how to find diameter of a circle. Hence, continue reading it and know **how to find the diameter of a circle** in a simple way.

**What Is Diameter in a Circle?**

Do you want to know what you call the line that halves a circle? Here’s your answer. This is the diameter of a circle that is represented by D. Simply expressed, the diameter of a circle is a straight line that passes through the middle of the circle to meet with the circumference lying on opposite sides. In other words, it can be defined as twice the length of a radius or the sum of two radii. So, this is the simple answer to your question **‘how to find the diameter of a circle.’**

The key difference between the two is length. The radius starts from the center of the circle and ends at the edge point where it touches the circle. In contrast to this, the diameter starts from one end of the circle to the other end of the circle.

**Some Common Terms You Should Know Before Moving Ahead**

Before you move to learn about the diameter formula and **how to find diameter,** you should learn some key terms. These terms will allow you to understand the complete study of the circle, including its diameter. Go over the following details to gain basic knowledge about the circle’s other dimensions:

**1. Radius (R or r)**

A radius is a line segment that joins the center of the circle with the edge of a circle. This is because it helps in measuring the area, diameter, and circumference of a circle. It is usually expressed by R or r in geometry.

**2. Circumference**

The Circumference or perimeter of the circle refers to the total length of the boundary of a circle. To calculate the circumference of the circle, you should know either its diameter or radius. If you know its diameter, then, its equation will be

C = (π) (d)

Now, let’s move on to the next section to find out **how to find the diameter of a circle. **

**Three Easiest Ways to Find the Diameter of a Circle with Examples**

Geometry is the easiest form of mathematics. Once you know its theories and minute concepts, then, it becomes very easy to solve geometrical figures’ riddles. Take a look at the following three easiest ways to find the diameter of a circle. Don’t forget to practice them today.

**1. Double the Radius**

Now, you know that the diameter is twice the length of the radius. If you know the radius of a circle, you will find the diameter in no time, using the formula given below:

D = RX 2

If the radius of a circle is 3 cm, use this formula in the following manner, and get the diameter:

D= 3×2 = 6

The diameter of the circle is 6.

**2. Divide the Circumference By PI(π)**

As you know diameter passes through the center to touch the circumference. Additionally, the circumference of a circle is the full length of the boundary of a circle. Consequently, you can find the diameter by dividing the circumference with pi. The value of pi is 3.14. The formula is as follows:

D = c ÷π

Suppose the circumference of the circle is 10 cm. The diameter of the circle will be

D = 10÷ 3.14 = 3.185

The diameter of the circle is 3.185 cm.

**3. Find it Through the Circle’s Area**

If you only know the area’s circle, you can easily find out the diameter. All you need to do is to divide the circle’s area by pi and then, you will do the result’s square root to find the radius. Once you know the radius of the circle, you will get the diameter by multiplying it by 2. The formula for finding the diameter through the circle’s area is as follows:

D = 2 × √(A/π)

Suppose the area of the circle is 20 cm2. First, you should divide it by π and get a result of 6.36 cm2. Then, do the square root of the result. Consequently, you will get the result of 40.58 cm. The radius of the circle is 40.58 cm and the diameter is 81.15 cm. Finally, you will get the diameter by multiplying the radius by 2.

**4. Calculate the Diameter by Drawing a Circle**

Have a ruler, a pencil, a paper, and a scale with you. Check out the following steps to calculate the diameter by drawing a circle:

- First of all, draw a circle
- Then, draw a horizontal line inside the circle. This line should pass through the circle, touching one edge to the other
- Label the endpoints where the line touches the circumference. Label them as A and B
- Then, draw overlapping circles. It means that your one circle’s center point should be A and another circle’s center point should be B.
- Then, draw a vertical line in a way that it should intersect the outer circles
- Now, you can measure the diameter.

**Conclusion**

So far this article has elaborated on how to find the diameter of a circle. Without knowing key concepts of geometry, it is impossible to acquire critical skills in solving geometrical figures.

The usage of diameter is not only useful for solving theoretical concepts but also for solving real-world engineering concepts. Please bookmark this article and practice what you have learnt here. The more you practice it today, the more you will get excellence in this concept. Hence, start practicing and keep learning.

**FAQs**

**1. What is the simple formula of a diameter?**

The simple formula of a diameter is d=2r. Simply put, it is double the length of radius.

**2. What is the simple formula for circumference to diameter?**

The quick and easy formula for measuring diameter with the value of circumference is C = πd

**3. What is the diameter of a 10 inch circle?**

If the radius of a circle is 10 inches, the diameter will be 20 inches.

**4. How to calculate mean diameter?**

To calculate mean diameter, you should add the two diameters and divide them by 2.

**5. Is the diameter half of the value of radius?**

Yes, the diameter is half of the value of radius.