Ever wondered what the numbers on the scope meant? When you buy a new scope, you’ll notice numbers on it. The numbers can sometimes be confusing for new users.
For proper use of the scopes, one needs to understand the meaning of scope numbers. You also need to know how to read and interpret them.
Scope numbers can be intimidating for new scope owners. However, that should not be the case.
In this post, I’ll break down the meaning of scope numbers, where to find them, and how to read them. Keep reading.
Main Contents
What are the scope numbers?

Even before we get started, let’s understand what scope numbers are.
Scope numbers are a set of numbers on a scope. The numbers are usually labeled on the name of a scope. For example, when buying a Leupold scope, you will see the numbers written as Leupold 3-9×40 scope.
So, what do scope numbers mean and how do you read them? Scope numbers stand for magnification and the objective lens diameter. The first numbers stand for a minimum magnification while the second ones stand for maximum magnification. Lastly, we have the numbers after the X that stand for objective lens diameter.
Let’s see why understanding scope numbers are important.
Importance of understanding scope numbers
Understanding scope numbers is important because it can affect the accuracy and precision of your shot. The higher the magnification power, the more details you can see on your target. But this gets you a narrower field of view.
The larger the objective lens diameter, the more light can enter the scope. This results in a brighter and clearer image. However, it also makes the scope heavier and bulkier.
Generally, understanding scope numbers give you better performances in different shooting situations. It means shooters understand the capabilities of their scope in situations like parallax adjustment, eye relief, and reticle type.
Lastly, having a better understanding of scope numbers will give you more confidence when shooting. You can make a more informed scope purchase decision. This also gets you targeting and shooting with confidence.
What are scope numbers?
In simple terms, scope numbers refer to the magnification power and objective lens diameter of the scope. The magnification power refers to how much the scope can zoom in on a target. The objective lens diameter on the other hand refers to the size of the front lens of the scope.
How scope numbers are assigned
Magnification power refers to how much the scope can zoom in on a target. It is usually denoted by a number followed by an “X”, such as 4X or 5X.
For example, a scope with a magnification power of 3X makes the image appear three times closer than it is.
Objective lens diameter refers to the diameter of the front lens of the scope, which determines how much light can enter the scope. It is usually denoted in millimeters (mm). Objective lens diameter is usually written after the magnification power with a dash. For example, 4x-32. In this example, the objective lens diameter is 32mm.
Understanding scope number format
Understanding the format of scope numbers is important when choosing a rifle scope. This is because it provides information about the scope’s magnification power and objective lens diameter. The format typically includes two numbers separated by an “x” or a dash as stated above.
Here are two format examples.
- 4×32 – For a fixed scope
- 6-24×50 – For a variable scope
The first number before the “X” or dash indicates the magnification power of the scope. For example, a scope with a magnification power of 4X will make the image appear four times closer than it is.
If the scope has a range of magnification powers, such as 6-24x, the first number indicates the lowest magnification power and the second number indicates the highest magnification power. In this example, the scope can be adjusted to magnify the image between 6 and 24 times.
The second number after the “x” or dash indicates the objective lens diameter of the scope. For example, a scope with an objective lens diameter of 32mm will allow light to enter through a lens that is 32mm in diameter. A larger objective lens diameter typically allows more light to enter the scope, resulting in a brighter and clearer image, but it also makes the scope heavier and bulkier.
Generally, understanding the format of scope numbers can help you choose a rifle scope matching your needs. You get to choose a scope based on its magnification power and objective lens diameter.
The scope number format includes different parts that provide information about the scope’s magnification power and objective lens diameter.
Understanding these parts can help you choose a rifle scope that is suitable for your shooting needs. The different parts of a scope number and what they mean are:
- Magnification power: This is the first number before the X
- Objective lens diameter: This is the second number after the X.
- Reticle: Some scope numbers may also include information about the reticle. These are usually the crosshairs or other markings used to aim at a target. Reticles can come in different shapes and sizes, and may also include illumination for low-light conditions.
- Other features: Depending on the manufacturer and model of the scope, the scope number may also include information about other features, such as the field of view, eye relief, parallax adjustment, and coating types.
Interpreting scope numbers Factors to consider
When interpreting scope numbers, there are several factors to consider. This is important to ensure that you choose a scope that is suitable for your intended use and shooting needs.
Below are some of the major factors to consider.
Understanding the range of a scope number
Scope numbers typically include a range of magnification powers and objective lens diameters. Understanding this range is important because it determines how the scope will perform in different shooting situations.
For example, a scope with a magnification power range of 4-16x is suitable for long-range shooting. On the other hand, a scope with a magnification power range of 1-4x is suitable for close-range shooting. So by understanding the numbers, you get to choose the right scope range for your needs.
If you’re shooting within a fixed range, then consider a scope with a fixed magnification. But for shooters with varying shooting ranges, a variable scope with a huge range is the best.
Identifying the intended use of a scope
Different types of shooting require different types of scopes. For example, if you are a hunter, the right scope is one with a low magnification power for quick target acquisition and a wide field of view. On the other hand, if you are a competitive shooter, you may need a scope with a high magnification power for precise aiming.
Determining the capabilities of a scope
In addition to magnification power and objective lens diameter, other factors that determine a scope’s capabilities include eye relief, reticle type, parallax adjustment, and coating type. Understanding these capabilities is important because they affect how the scope performs in different shooting conditions.
Assessing the quality of a scope
The quality of a scope is determined by several factors. Common factors include the materials used, the manufacturing process, and the brand reputation.
A high-quality scope is more durable, accurate, and reliable than a lower-quality scope. It can withstand a few falls and harsh climatic conditions. But it also comes with a higher price tag.
Common misconceptions about scope numbers
There are several common misconceptions about scope numbers that can lead to confusion and incorrect assumptions. These misconceptions include:
Misunderstanding the meaning of a scope number
One common misconception is that the first number in a scope number indicates the distance at which the scope is accurate. However, this is not true.
The first number in a scope number indicates the magnification power of the scope, while the second number indicates the diameter of the objective lens.
Confusing scope numbers with other specifications
Another common misconception is that the scope number is the only important specification to consider when choosing a scope. However, there are several other specifications, such as eye relief, reticle type, and parallax adjustment, that are also important to consider.
Believing that higher scope numbers are always better
Many people believe that a higher scope number always means a better scope. However, this is not necessarily true. A higher magnification power and larger objective lens can provide a clearer image.
However, they also make the scope heavier, bulkier, and more expensive. Additionally, a higher magnification power can make it more difficult to aim accurately, especially at close range.
Conclusion
Correctly interpreting scope numbers is crucial for selecting a scope that meets your shooting needs and provides the performance you require. By understanding the different parts of a scope number and what they mean, you can choose a scope that is appropriate for your intended use and shooting needs.
There are several benefits to reading the scope numbers. You get to enjoy improved accuracy, confidence, and better performances in different shooting situations.

Travis Mike is a firearm enthusiast and author passionate about all things guns. With 10 years of experience in the industry, Travis Mike has gained a wealth of knowledge on the subject. He is skilled in gunsmithing and tactical training. In addition to professional experience, Travis Mike is an avid hunter and shooter, regularly participating in local shooting ranges and hunting trips.