minuteofangle

Minute of angle, commonly abbreviated MOA, is an angular unit used in shooting, optics, and ballistics. It represents one sixtieth of a degree and corresponds to a small arc at a given distance. As an angular measure, MOA is distance‑independent, allowing it to be translated into different linear sizes at various ranges. It is widely used to describe sight adjustments, group sizes, and aiming corrections.

At 100 yards, 1 MOA subtends about 1.047 inches; at 100 meters, about 2.91 centimeters. In general, 1 MOA at a distance D (in yards) corresponds to D/100 inches. In metric terms, 1 MOA is about 0.2909 milliradians (mrad). Since 1 degree equals 60 minutes, 1 MOA also equals one arcminute of angle.

Common usage includes rifle scope adjustments and reticle markings. Many scopes are designed with adjustment increments of 1/4 MOA, 1/2 MOA, or 1 MOA per click. A group size described as 2 MOA, for example, corresponds to roughly 2 inches wide at 100 yards (or about 2 cm at 100 meters).

MOA is often contrasted with metric angular units such as milliradians or mils, which serve similar purposes in long‑range shooting. While convenient for practical zeroing and correction, MOA measurements assume ideal conditions; actual results depend on ballistic performance, wind, parallax, and shooter consistency. The unit remains a standard reference for assessing and communicating aiming accuracy.