Mil-Dot Range Calculator
Calculator Inputs
Measure the known height or width of the target. Use a reference object if actual size is unknown.
Count how many mil spacings the target spans in your scope. Read to 0.1 mil precision or better.
Enter Your Values
Select a solve mode, fill in the known values (target size and mils observed, or range and mils, etc.), and the result will appear here automatically.
Important
This calculator is provided for general information only and is not financial, tax, or legal advice. Results are estimates and do not reflect your full circumstances, current rates, fees, or eligibility rules. Speak to a qualified professional before making a financial decision.
Estimate target range using MIL/MRAD or MOA reticle measurements
The mil-dot range calculator is an essential tool for long-range shooters, hunters, military and law enforcement snipers, and anyone who uses a rifle scope with a mil-dot or MOA reticle. By applying the fundamental angular relationship between target size, angular measurement, and distance, you can quickly and accurately estimate the range to a target — without a rangefinder. The underlying principle is deceptively simple: if you know how large a target is and how many mils it subtends in your reticle, you can calculate exactly how far away it must be. One milliradian (mil or MRAD) is an angular unit equal to 1/1000 of a radian. At 1,000 yards, 1 mil subtends exactly 36 inches. At 100 yards, 1 mil equals 3.6 inches. This linear relationship makes the math straightforward and the mental arithmetic manageable even in the field. The metric formula is the most elegant: Range (meters) = Target Size (meters) × 1000 / Mils Observed. The imperial equivalent substitutes a conversion factor: Range (yards) = Target Size (inches) × 27.78 / Mils. The constant 27.78 comes from dividing 1000 by 36 (since one yard equals 36 inches). Both formulas are derived from the same radian geometry. This calculator goes beyond the basic formula. It supports three solve modes — find range, find target size, or find the required mils reading — making it a complete three-way solver for any two-of-three scenario. It handles both MIL/MRAD and MOA reticle types, with three MOA formula variants (basic × 100, standard × 99.5, and the most accurate precise × 95.5). It automatically corrects for Second Focal Plane (SFP) scope magnification: on an SFP scope, the reticle subtensions are only accurate at the rated maximum magnification, so the calculator scales your observed mils by the ratio of maximum to current magnification. Target presets cover the most common real-world scenarios: military silhouettes (NATO E-type and F-type), human body dimensions, hunting targets (whitetail deer, mule deer, elk, coyote, prairie dog, wild boar), and vehicle reference points (license plates, sedan width, tank width). Selecting a preset auto-fills the target size field, saving time when you already know your reference target. The results include the primary calculated value, the same value converted to alternate units, the angular equivalence between mils and MOA, a formula display showing the actual numbers substituted, an error confidence band showing how much range error results from a ±0.1 mil reading uncertainty, a visual mil-dot reticle diagram, a subtension reference chart showing 1-mil subtension at five standard distances, and a quick-reference range table across common mil readings for your specific target size. Understanding the difference between First Focal Plane (FFP) and Second Focal Plane (SFP) scopes is critical to correct range estimation. FFP scopes scale the reticle with magnification, so the subtensions remain accurate at any power setting. SFP scopes keep the reticle size constant in the eyepiece while the image magnifies, so subtensions are only correct at the rated magnification. Many budget and mid-range scopes are SFP — if you try to range estimate at anything other than maximum magnification, your answer will be wrong by the magnification ratio. This calculator handles that correction automatically. For MOA reticles, the precise formula uses the multiplier 95.5, derived from the fact that one true MOA equals 1.0472 inches at 100 yards (100 / 1.0472 ≈ 95.5). The simplified version uses 100, treating 1 MOA as exactly 1 inch per 100 yards — a useful approximation for quick field estimates but less accurate at long range. The standard version uses 99.5 as a compromise. Accuracy of range estimation depends heavily on the precision of your target size estimate and your mil reading precision. Most scopes allow reading to 0.1 mil; some premium scopes allow 0.05 mil. A 0.1 mil reading error at 2.0 mils observed represents a 5% range error — at 500 yards, that is 25 yards of uncertainty. Knowing this error bound helps you make informed decisions about when to use estimated range versus a laser rangefinder.
Understanding Mil-Dot Range Estimation
What Is a Mil-Dot Reticle?
A mil-dot reticle is a rifle scope crosshair with small dots or hash marks spaced exactly 1 milliradian apart. One milliradian (mil or MRAD) is an angular unit equal to 1/1000th of a radian. The key property of milliradians is that the physical size they subtend at a target scales linearly with distance: 1 mil = 10 cm at 100 meters, 20 cm at 200 meters, 1 meter at 1,000 meters. In imperial units, 1 mil = 3.6 inches at 100 yards, 36 inches at 1,000 yards. By counting how many mil-dot spacings fit across a target of known height or width, you can calculate the range. MOA (Minute of Angle) reticles work on the same principle, using MOA units where 1 MOA ≈ 1.047 inches at 100 yards, or exactly 1/60th of a degree.
How Is Range Calculated?
The core formula derives directly from the definition of the milliradian. Since 1 mil subtends 1 unit at 1,000 units of distance, the general relationship is: Observed Mils = Target Size / Range (all in the same unit system). Rearranging gives Range = Target Size / Mils × 1000 (metric, meters) or Range = Target Size × 27.78 / Mils (imperial, inches to yards). For MOA reticles, the precise formula is Range (yards) = Target Size (inches) × 95.5 / MOA. For SFP scopes, the observed mils must first be corrected by multiplying by the ratio of maximum to current magnification. The three-way solver inverts these formulas: to find target size, multiply range by mils and divide by the appropriate constant; to find mils, multiply target size by the constant and divide by range.
Why Range Estimation Matters
Accurate range estimation is fundamental to precision shooting. Bullet trajectory is parabolic — the drop at 500 yards can be many feet for typical rifle calibers. Without knowing the range, you cannot correctly dial in your elevation or apply the right holdover. While laser rangefinders are excellent tools, batteries can die, reflective surfaces can fool them, and in some tactical situations the laser emission itself is a liability. Mil-dot ranging is a passive, silent, battery-free technique that works in any lighting condition. For hunters, it helps ensure ethical shot placement at extended ranges. For long-range competition shooters, it provides a backup to electronic systems. For military and law enforcement snipers, it is a core skill taught in all professional sniper schools.
Limitations and Sources of Error
The accuracy of mil-dot ranging depends on two key inputs: target size estimate and mil reading precision. Target size must be known or estimated — an error of 10% in target size directly causes a 10% range error. Mil readings can typically be made to 0.1 mil precision visually; interpolating to 0.05 mil is possible with practice. A 0.1 mil reading error at 2 mils observed produces about a 5% range error. At 500 yards, this is ±25 yards — sufficient for most hunting but potentially significant for precision long-range work. SFP scope users must be disciplined about shooting at maximum magnification for ranging or correctly applying the magnification correction. Environmental factors (mirage, heat shimmer, low light) reduce ranging precision. For critical applications, laser rangefinders or known-distance markers should confirm estimated ranges.
Formulas
The fundamental mil-ranging equation. Since 1 mil subtends 1 meter at 1,000 meters, dividing target size by mils and multiplying by 1,000 yields range in meters.
Imperial variant where the constant 27.78 = 1000 / 36 (since 1 yard = 36 inches). Converts target size in inches directly to range in yards.
Most accurate MOA formula using the true MOA constant: 1 MOA = 1.0472 inches per 100 yards, so the multiplier is 100 / 1.0472 ≈ 95.5.
Second Focal Plane scopes require correction when ranging at non-max magnification. The reticle subtension scales inversely with magnification ratio.
Reference Tables
1 Mil Subtension at Standard Distances
| Distance | 1 Mil Subtends (Imperial) | 1 Mil Subtends (Metric) |
|---|---|---|
| 100 yards / meters | 3.6 inches | 10 cm |
| 200 yards / meters | 7.2 inches | 20 cm |
| 300 yards / meters | 10.8 inches | 30 cm |
| 500 yards / meters | 18.0 inches | 50 cm |
| 1,000 yards / meters | 36.0 inches | 100 cm (1 m) |
Common Target Sizes for Range Estimation
| Target | Size (inches) | Size (cm) | Use Case |
|---|---|---|---|
| NATO E-type silhouette | 20" | 51 cm | Military range estimation |
| Human shoulder width | 18" | 46 cm | Tactical / LE |
| Whitetail deer chest | 18" | 46 cm | Hunting |
| Elk chest depth | 24" | 61 cm | Hunting |
| US license plate width | 12" | 30.5 cm | Vehicle reference |
| Sedan width | 72" | 183 cm | Vehicle reference |
Worked Examples
Ranging a Deer with MIL Reticle
Formula: Range (yd) = Target Size (in) × 27.78 / Mils
Range = 18 × 27.78 / 1.5
Range = 500.04 / 1.5
Range = 333.4 yards
SFP Scope Correction at Half Magnification
SFP correction: True Mils = 2.0 × (12 / 6) = 4.0 mils
Formula: Range (yd) = 20 × 27.78 / 4.0
Range = 555.6 / 4.0
Range = 138.9 yards
MOA Reticle Range Estimation
Precise MOA formula: Range (yd) = Target Size (in) × 95.5 / MOA
Range = 24 × 95.5 / 6.5
Range = 2,292 / 6.5
Range = 352.6 yards
How to Use the Mil-Dot Range Calculator
Choose Your Solve Mode
Select what you want to calculate: 'Find Range' (most common — you know target size and mils), 'Find Target Size' (you know range and mils, e.g. to identify an unknown object), or 'Find Mils / MOA' (you know both range and size and want to pre-calculate the expected reticle reading).
Set Reticle Type and Scope Settings
Choose MIL/MRAD or MOA to match your scope's reticle. For MOA, select the formula variant (Precise × 95.5 is most accurate for long range). If your scope is Second Focal Plane (SFP), enable SFP mode and enter the scope's maximum magnification and your current magnification — the calculator will auto-correct your observed mils.
Enter Target Size and Reticle Reading
Type in the target's known height or width in inches (imperial) or centimeters (metric). Alternatively, select a preset from the military, hunting, or vehicle library to auto-fill the field. Then carefully measure how many mil (or MOA) divisions the target spans in your scope, reading to at least 0.1 mil precision. Enter this as your mils or MOA observed.
Read Your Results
The calculator instantly shows the range in both yards and meters, the angular subtension in both mils and MOA, the SFP-corrected mils if applicable, the exact formula used with your numbers substituted, and the ±0.1 mil reading error uncertainty as a percentage. The subtension chart and range table provide quick-reference context for your specific scenario.
Frequently Asked Questions
What is the difference between MIL/MRAD and MOA reticles?
Both MIL (milliradian) and MOA (Minute of Angle) are angular units used to measure scope reticle subtensions and turret adjustments. One MIL equals 3.438 MOA. In practical terms, 1 MIL subtends 10 cm at 100 meters (3.6 inches at 100 yards), while 1 MOA subtends approximately 2.91 cm at 100 meters (1.047 inches at 100 yards). MIL-based systems are common in military and long-range precision shooting communities, especially those using metric measurements. MOA-based systems are prevalent in traditional American hunting and competitive shooting. The ranging formulas differ but the underlying geometry is identical — both are angular measurements of the same physical relationship between target size and distance.
Why does my SFP scope give wrong range estimates at low magnification?
Second Focal Plane (SFP) scopes keep the reticle physically the same size in the eyepiece regardless of magnification, while the image of the target scales up. This means the reticle subtensions — the mils or MOA spacings between the dots or hash marks — are only correct at one specific magnification, typically the maximum rated power. At half the rated magnification, 1 mil in your reticle actually subtends 2 true mils on the target. This calculator's SFP correction multiplies your observed reading by the ratio of max magnification to current magnification to give you the true angular subtension. Always range estimate at maximum magnification on an SFP scope, or apply this correction factor.
Which MOA formula variant should I use?
The Precise × 95.5 formula is the most accurate and is recommended for long-range shooting. It uses the true value of 1 MOA = 1.0472 inches per 100 yards, giving 100 / 1.0472 ≈ 95.5 as the multiplier. The Basic × 100 formula approximates 1 MOA as exactly 1 inch per 100 yards — an easy mental math shortcut that introduces about 4.7% error at all distances. The Standard × 99.5 is a compromise used in some references and apps. At short ranges (under 300 yards) the difference between variants is small; at 800–1,000 yards the 4.7% error from the basic formula could mean 40+ yards of uncertainty in your range estimate.
How accurate is mil-dot range estimation compared to a laser rangefinder?
Laser rangefinders can typically range to within 1 yard at practical distances, making them far more accurate than optical mil-dot ranging. Mil-dot ranging accuracy depends on two factors: your knowledge of the target's true size, and your precision in reading the mils. A 10% error in target size estimate gives a 10% range error. Reading to 0.1 mil precision at 2 mils observed introduces about 5% range uncertainty (±25 yards at 500 yards). Despite lower absolute accuracy, mil-dot ranging has important advantages: no battery dependency, no laser emission signature, passive technique that works in all lighting conditions, and no glare from reflective surfaces. Many professionals use both — a laser for known targets and mil-dot as backup.
What target size should I use for a deer?
The most common reference measurement for whitetail deer is the chest depth (brisket to spine), which averages about 18 inches (45.7 cm) for a mature deer. This is preferable to total body height because it's more consistent between animals and is the shot-zone measurement relevant for ethical hunting. Mule deer chest depth is approximately 20 inches (50.8 cm) and elk is about 24 inches (61 cm). The shoulder height of a deer is also used by some hunters — typically 36–40 inches for a whitetail — but it varies more with posture and terrain. The calculator's preset library includes these values. Always use the dimension you can most accurately see and measure in the scope — chest depth is usually the most reliable for ranging because the animal's silhouette clearly shows this measurement.
Can this calculator help with holdover calculations?
The mil-dot ranging calculator focuses on the range estimation problem. Holdover (bullet drop compensation) is a separate calculation that requires ballistic data: your bullet's velocity, ballistic coefficient (BC), zero distance, and atmospheric conditions. Once you have an accurate range from this calculator, you would apply that range to your ballistic table, firing solution software (like Applied Ballistics, Hornady 4DOF, or similar), or pre-computed dope card to determine the correct elevation correction in mils or MOA. The subtension reference chart in results does show how many inches one mil covers at various distances, which helps you translate bullet drop data (in inches) into mil holdover values. For example, if your ballistic table shows 36 inches of drop at 1,000 yards, you need 1 mil of holdover at that distance.