Enter the known object height (in meters) and the angular height in Mils from your binocular reticle to calculate the distance to the object. Results are shown in both meters and kilometers using the standard mil-based range formula.
Distance to Object
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Distance in Kilometers
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Distance in Yards
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The calculator uses the mil-based range formula: D = (OH / Mil) × 1000, where OH is the known object height in meters, Mil is the angular height read from the binocular reticle in mils, and D is the resulting distance in meters. One mil represents the angle subtended by 1 meter at a distance of 1000 meters.
A mil (milliradians or mrad) is a unit of angular measurement used in military and tactical optics. One mil is equivalent to 1 meter of height or width at a distance of 1000 meters. Binoculars with a mil-dot or mil-scale reticle allow you to measure the angular size of an object and estimate its range.
Most ranging binoculars display a horizontal or vertical scale in the field of view. Align the bottom of the scale with the base of the target and read how many mil marks the object spans vertically. Common mariner 7×50 binoculars, for example, have marks spaced 5 mils apart. Fractional readings can be estimated between marks.
You can use standard reference heights for common objects. A typical human adult is about 1.7–1.8 m tall, a car is roughly 1.5 m high, and a two-story building is around 6–7 m. Using a well-known reference object near your target can also help you estimate height more accurately.
The range formula works with any binoculars that have a mil-based reticle scale. Standard binoculars without a reticle cannot provide a mil reading, so the formula does not apply. Military, marine, and hunting binoculars commonly include mil-dot or ranging reticles.
Accuracy depends on how precisely you know the object's true height and how accurately you read the mil scale. Small errors in either value are amplified at longer distances. For best results, use objects with well-known heights and read the reticle carefully, ideally resting the binoculars on a stable surface.
Mils (milliradians) and MOA (minutes of angle) are both angular units used in optics and shooting, but they differ in size. One mil equals approximately 3.44 MOA. The mil system is metric-friendly since 1 mil = 1 m at 1000 m, making the range formula straightforward. MOA is commonly used in US rifle scopes.
Yes — the mil-based range formula is the same method used in naval and military range finding. Marine 7×50 binoculars were specifically designed with mil scales for estimating distances to ships and landmarks. Simply enter the known height of the vessel or structure and the mil reading from your reticle.