MOA Calculator — Minute of Angle

Q: What is MOA in shooting?

MOA is an acronym for Minute of Angle . It’s an angular measure commonly used in shooting. 1 MOA refers to an angle of 1 minute of arc, which is 1/60 of a degree. Knowing the MOA of our rifle, we can quickly estimate the spread of our shots at a given distance.

Q: What is 1 MOA at 100 yards?

1 MOA at 100 yards equals around 1 inch . As MOA is an angle of 1 minute of arc, the result is the spread at the given distance. The longer we go, the greater the spread, roughly 1″ per 100 yd.

Creators

Wojciech Sas, PhD

Wojciech SasPhD, Institute of Physics in Zagreb

Wojciech, PhD, is a physicist at the Institute of Physics in Zagreb, investigating materials under extreme conditions such as low temperatures and high pressures. He specializes in experimental work, including participation in Large-scale User Facilities such as synchrotrons. Wojciech uses his experience and knowledge to create calculators in physics, math, and statistics categories. In his free time, he likes swimming, playing board games, and looking for meteors while stargazing. See full profile

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Reviewers

Steven Wooding

Steven Wooding is a physicist by training with a degree from the University of Surrey specializing in nuclear physics. He loves data analysis and computer programming. He has worked on exciting projects such as environmentally aware radar, using genetic algorithms to tune radar, and building the UK vaccine queue calculator. Steve is now the Editorial Quality Assurance Coordinator here at Omni Calculator, making sure every calculator meets the standards our users expect. In his spare time, he enjoys cycling, photography, wildlife watching, and long walks. See full profile

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Welcome to our MOA calculator, a great tool that helps you estimate the spread at a specific distance while shooting. If you are curious about what MOA is, how to calculate MOA at any distance, or what the MOA calculation formula is, then search no more — we will explain everything in the following sections.

Thanks to the quick unit conversion, you can also use it as a MIL-to-MOA calculator or an inches-to-MOA calculator — the choice is yours.

So wait no more, and let’s learn something new about MOA.

What is MOA in shooting?

MOA is an acronym for Minute of Angle. It’s an angular measure commonly used in shooting. 1 MOA refers to an angle of 1 minute of arc, which is 1/60 of a degree. Knowing the MOA of our rifle, we can quickly estimate the spread of our shots at a given distance.

If you want to know more about other angular measures, check our angle conversion calculator.

MOA calculation formula

There is a simple formula that helps you correlate MOA and spread for any shooting distance:

s = MOA × d / 100

where:

s — Spread of shooting in inches; and
d — Distance in yards.

It means that for each additional MOA, the spread increases by 1″ for every 100 yd.

However, it’s worth mentioning that the above formula is only a fair approximation. The exact value takes into account that the spread is actually an arc length (you can read more about the topic at arc length calculator). The equation is:

s = π × MOA × d / 10800

By rearranging this equation, the formula for MOA is:

MOA = s × 10800 / (π × d)

Here, the MOA is still measured in minutes of arc, while the units of spread and distance can be any, as long as they are the same.

How to use MOA calculator

Let’s practice together and see how to calculate MOA at any distance. Imagine we want to estimate MOA at 1000 yards with a 10″ spread. To use Omni’s MOA calculator at 1000 yards:

Input distance equal to 1000 yards.
Type 10 inches for the spread.
And that’s it — The resulting MOA will display immediately. The outcome is about 0.955 arcmin.

The good thing is that our tool works in other ways as well. You simply need to fill in two of the three fields, and it will evaluate the remaining one.

🙋 In terms of precise shooting, you should always keep in mind the gravity. Check our projectile range calculator to estimate the shooting angle or to work out the maximal range.

MIL to MOA calculator

Our tool can also serve as an MIL-to-MOA calculator. MIL (also known as mrad) is another unit of measure for an angle, equal to 1/6400 of a radian. The relationship is the following:

1 MIL = 1 MOA × (10.8 / π)

To get a rough estimation, we can write that:

1 MIL ≈ 3.438 MOA; or

1 MOA ≈ 0.291 MIL.

You can swiftly switch between them by selecting the appropriate units at the MOA field.

FAQs

How do I calculate MOA at different distances?

To estimate the spread of 1 MOA at different distances, use the following values:

At 100 yards, 1 MOA equals about 1″.
At 200 yards, 1 MOA equals about 2″.
At 300 yards, 1 MOA equals about 3″.

As a rule of thumb, the spread increases by 1″ for every 100 yards.

Can I use MOA red dot to estimate range?

Yes. If the red dot corresponds to 1 MOA, you can assess the distance to the object if you know its true size:

Let’s say that the actual size is 20″.
If you can squeeze 4 red dots inside the object while looking through the scope, it equals 4 MOA.
By applying the MOA calculation formula, we can estimate the distance:

d = s / MOA × 100
The distance equals about:

d = 20 / 4 × 100 = 500 yd

What is 1 MOA at 100 yards?

1 MOA at 100 yards equals around 1 inch. As MOA is an angle of 1 minute of arc, the result is the spread at the given distance. The longer we go, the greater the spread, roughly 1″ per 100 yd.