What is MOA?
Minutes of Angle for Red Dot Sights
If you’re shopping for a red dot sight, you have probably seen an MOA number listed in the product description. You might be thinking, “What is MOA and why is it important? Which MOA should I select for my red dot?” In this article, we explain MOA in simple terms and graphics so you can feel better equipped in your red dot sight buying decision.
There are 360 degrees in a circle. Now take one of those degrees and divide it into 60 equal parts. Just one of those parts (1/60th) is one Minute of Angle or MOA.
The term “minute” simply means 1/60th. As a measurement of time, a minute is 1/60th of an hour. As an angular measurement, a minute is 1/60th of a degree.
Minute of Angle (MOA) is 1/60th of 1 degree in a circle
MOA and Distance
Imagine holding two laser pointers at 1/60th of a degree from each other and aiming them at a wall that is 100 yards away. The distance between the two dots as they shine on the wall would be 1.047 inches.
Using this distance as the diameter of a circle, we would round down to say that the circle is 1 inch or 1 MOA.
If we push back our wall to 200 yards, the distance between the dots (the diameter of our circle) will double in size. So then 1 MOA is 2 inches at 200 yards, 3 inches at 300 yards, 4 inches at 400 yards, and so on.
MOA is not dependent on distance
MOA is not dependent on distance, but distance determines the size of MOA. For example, at 800 yards, 1 MOA is still 1 MOA, but it’s 8x larger than it is at 100 yards. See the following table.
MOA for Red Dot Sights
An MOA number listed on a red dot sight refers to how large the dot will appear on a target that is 100 yards away.
Since we know that 1 MOA is 1 inch at 100 yards, a red dot listed as 3 MOA will appear 3 inches in diameter at 100 yards, 6 inches at 200 yards, and 9 inches at 300 yards.
Choosing the “right” MOA is all about preference. If you shoot primarily at longer ranges, you may find a smaller dot more suitable. A 1-MOA dot will cover less of the target at longer distances than a 6-MOA dot. But at closer ranges, a larger MOA dot may be preferred. A middle-ground around 3 MOA is great for both home defense and longer-range target shooting.
- 1 MOA is 1 inch at 100 yards
- MOA is not dependent on distance
- There is no “right” or “wrong” MOA; it’s all about preference
- Lower MOA is preferable for longer ranges
- Higher MOA is preferable for shorter ranges
- A 3-MOA red dot is good for both long and short ranges