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MOA to Mil Converter

Last updated Researched from published specifications and owner reviews, not tested in person

Quick answer

One mil equals 3.43775 MOA at every distance, because both are angles and the ratio never changes. At 100 yards 1 MOA subtends 1.047 inches and 1 mil subtends exactly 3.6 inches. The common shorthand of 1 inch per MOA is 4.5 percent small and costs you 14 inches on a 30 MOA come-up at 1,000 yards.

Two angular units are in daily use and they are not interchangeable. A minute of angle is one sixtieth of a degree. A milliradian is one thousandth of a radian. Both describe an angle, so both cover more ground the further away the target is, in direct proportion to distance.

The MOA figure comes from trigonometry: 2 times 3600 inches times the tangent of half a minute gives 1.047 inches at 100 yards. The mil figure needs no trigonometry at all, because a milliradian is by definition one thousandth of the distance to the target, and one thousandth of 3,600 inches is exactly 3.6.

That difference is why mils are easier to compute in your head, and why the 1 inch shorthand for MOA exists at all.

MOA, mil and inch converter

Result

1.05 in

The formula

MOA inches = amount x 1.047197 x (yards / 100)    mil inches = amount x 3.6 x (yards / 100)

Scopes and levels that make these numbers usable

Top matches update when you change your numbers.

Where the shooter shorthand stops being harmless

Treating a minute of angle as exactly one inch per hundred yards is called shooter MOA or inches per hundred yards. It is 4.5 percent small, and the last column is what that costs per minute of angle.

At 1,000 yards, 1 MOA is 10.47 inches and the shorthand gives 10, so a 30 MOA come-up computed in shorthand is about 14 inches short.

Sourced figure

True MOA against the 1 inch convention
DistanceTrue MOA1 milShooter MOAError per MOA
100 yd1.05 in3.6 in1 in0.05 in
200 yd2.09 in7.2 in2 in0.09 in
300 yd3.14 in10.8 in3 in0.14 in
400 yd4.19 in14.4 in4 in0.19 in
500 yd5.24 in18 in5 in0.24 in
600 yd6.28 in21.6 in6 in0.28 in
800 yd8.38 in28.8 in8 in0.38 in
1000 yd10.47 in36 in10 in0.47 in

The error is per minute of angle, so it multiplies by however much you dial. Inside 300 yards it is smaller than a group. Past 600 it is one of the larger avoidable errors in the shot.

Which unit should you use?

Neither is more accurate. What matters is that your reticle and your turrets use the same unit, so a correction you read off the glass is a correction you can dial without arithmetic.

A mil reticle with MOA turrets means multiplying every reading by 3.43775, in the field, under time pressure, with cold hands. That is where errors come from, and it is a configuration you should simply never buy.

Beyond matching, mils have a small practical edge: the constant is a round 3.6 and the ranging constant is a round 27.78, which are easier to hold in your head than 1.047 and 95.49. MOA has finer common click values, a quarter MOA being 0.26 inches at 100 yards against 0.36 for a tenth mil, though on most targets that difference is academic.

The conversions worth memorising

One mil is 3.43775 MOA and one MOA is 0.29089 mil, at every distance without exception.

Sourced figure

Fixed relationships between the units
FromToMultiply by
MilsMOA3.43775
MOAMils0.29089
MOAInches at 100 yd1.047198
MilsInches at 100 yd3.6
MilsCentimetres at 100 m10
MOADegrees0.016667

Every figure here is exact rather than rounded convention, except where the decimal itself has been truncated for reading.

Sources

  • Definition of a minute of angle, one sixtieth of one degree
  • Definition of a milliradian, one thousandth of a radian

Frequently asked questions

How many MOA is 1 mil?

One mil is 3.43775 MOA, at every distance. Both are angular units, so the ratio between them is fixed and does not change with range. To go the other way, one MOA is 0.29089 mil. These two numbers are worth memorising if you own a scope whose reticle and turrets disagree.

Is 1 MOA exactly 1 inch at 100 yards?

No. It is 1.047 inches, and the difference is exact trigonometry rather than a matter of opinion. The 1 inch figure is a convention called shooter MOA or inches per hundred yards. It is harmless inside about 300 yards and it costs roughly 14 inches on a 30 MOA come-up at 1,000 yards.

Why is a mil exactly 3.6 inches at 100 yards?

Because a milliradian is defined as one thousandth of a radian, and at the small angles involved that means one thousandth of the distance to the target. One hundred yards is 3,600 inches, and one thousandth of 3,600 is 3.6. No trigonometry is involved, which is what makes mil arithmetic simpler to do in your head.

Which is better for long range shooting?

Whichever your scope uses consistently. Competitive precision shooting has largely standardised on mils, mostly because the round constants make spotting and correcting faster when calling for another shooter. Hunting in North America still skews MOA. Neither choice will cost you a hit if the reticle and turrets agree.

How do I convert a mil hold to MOA clicks?

Multiply the mils by 3.43775 to get MOA, then divide by your click value. A 1.5 mil hold is 5.16 MOA, which on a quarter MOA turret is 20.6 clicks, so 21. Doing this under time pressure is exactly why a matched reticle and turret is worth more than any other feature on the scope.

Does the unit affect how precisely I can adjust?

Slightly, and less than people think. A quarter MOA click moves 0.26 inches at 100 yards and a tenth mil click moves 0.36 inches, so MOA turrets are marginally finer in their most common form. On any target large enough to shoot at, that difference is smaller than the rifle and the shooter contribute.

Researched, not professional advice. This page is compiled from published manufacturer specifications, published optical and ballistic formulas, and owner-review consensus, not hands-on testing. Figures described as a rule of thumb are shooter convention rather than sourced numbers, and they are labelled that way wherever they appear. Ballistic figures come from a point mass model using the ballistic coefficient the maker publishes, so treat them as a starting point and confirm them on paper at a measured distance. Confirm your firearm is unloaded with the action open before you mount, level, torque or bore sight anything. Verify a zero only on a supervised range or a safe, legal backstop, know what lies beyond your target, and follow the law where you hunt and shoot, including rules on land access and permitted cartridges.