MOA Calculator (Minute of Angle)
Find the size a minute of angle covers at a distance.
A minute of angle is 1/60 of a degree — a common unit for shooting accuracy.
How the Math Works
The MOA Calculator uses a precise trigonometric formula to determine the physical size that one Minute of Angle covers at any given distance. The formula size = MOA × 1.047 × (distance ÷ 100) is derived from the fact that 1 MOA equals approximately 1.047 inches at 100 yards. When you multiply the desired MOA by this constant and adjust for distance (dividing by 100 and multiplying by the actual distance), you're essentially scaling the angular measurement to a linear size. This mathematical relationship transforms angular precision into tangible, measurable dimensions that shooters can use for equipment adjustments.
Practical Applications
To use this calculator practically, first determine your shooting distance in yards or meters, then decide how much adjustment you need in MOA. For example, if your shot group is 3 inches low at 300 yards, you'd calculate: 3 = MOA × 1.047 × 3, which gives you approximately 0.95 MOA adjustment needed. Most rifle scopes adjust in 0.25 MOA increments, so you'd need roughly 4 turret clicks. This calculation also helps determine your scope's adjustment range, reticle subtensions, or bullet drop compensation at various distances, making it essential for precision shooting and ballistics planning.
Day-to-Day Use
Beyond shooting sports, MOA calculations appear in many everyday scenarios where angular measurements matter. Surveyors use similar principles to measure land boundaries, astronomers calculate angular distances between celestial objects, and photographers apply comparable math when determining field of view or depth of field. Even in construction, understanding how angles translate to physical measurements at distance helps with layout work and precision fitting. The MOA Calculator serves as an educational tool, demonstrating how abstract mathematical concepts connect to practical measurement challenges we encounter when we need to translate between angular observations and real-world dimensions.
Worked example
1 MOA at 300 yd → about 3.14 inches.
FAQ
Is 1 MOA exactly 1 inch?
Close — the true value is 1.047 inches per 100 yards.