mildot

MilDot is a type of reticle used in rifle scopes that relies on milliradian-based markings to estimate range, track moving targets, and apply ballistic holds. The reticle typically features a vertical and horizontal scale with marks every 1 mil (one thousandth of a radian) and one or more central dots known as Mil-Dots. Because 1 mil subtends about 1 meter at 1000 meters of distance, targets of known height that appear to cover a given number of mils can be ranged quickly.

To estimate range, the shooter measures how many mils the target occupies on the reticle; range in meters is approximately (target height in meters × 1000) divided by the observed mil count. For example, a 1.8-meter tall target spanning 3 mils would be about 600 meters away. Once range is known, the shooter can apply a holdover or adjust elevation and windage using the same mil-based scale, without re-aiming.

Variants vary in how many dot markers exist, spacing, and whether the same mils are used on both axes. Mil-Dot reticles are common in tactical and sport shooting and are often paired with ballistic calculators or muzzle velocity data.

Limitations include the need for accurate target size estimation, proper magnification, and parallax control; accuracy decreases with target size errors, mirage, and improper understanding of mil arithmetic. They are typically contrasted with MOA-based reticles, which use minutes of angle instead of mils.