MOA, MRAD and Dot Size in One Conversion Table
1 MOA is 1.047in at 100 yards; 1 mil is 3.6in at 100 yards. A 1/4 MOA click moves impact 0.262in per 100 yards, a 0.1 mil click moves it 0.36in. The same arithmetic governs reticle subtension, which is why a 2 MOA dot covers 2.09in at 100 yards and completely hides a 6in plate at 287.
One minute of angle subtends 1.047 inches at 100 yards. One milliradian subtends 3.6 inches at 100 yards, exactly, because a mil is one part in a thousand and 100 yards is 3,600 inches. Everything else on this page is those two numbers multiplied by something.
The reason people stay confused is that the industry teaches turrets and reticles as separate subjects. They are not. A 2 MOA dot and a 2 MOA turret correction are the same angular quantity pointed at different jobs, and once you see that, the question of whether your dot is precise enough for a given target stops being a matter of taste and becomes a division problem.
Both units work. Neither is more accurate. The only thing that genuinely matters is that your turret and your reticle speak the same language, and the failure mode below is what happens when they do not.
Two definitions, one difference that actually matters
A minute of angle is 1/60th of a degree. The true subtension is 1.0472 inches per 100 yards; the shooting world rounds it to 1.047, and a fair number of scope makers round it all the way to 1.000 and call it a Shooter's MOA or IPHY. That last group is a real source of tracking error and you should know which kind your scope has.
A milliradian is 1/1000th of a radian. At any distance, 1 mil covers 1/1000th of that distance. Ten centimetres at 100 metres. 3.6 inches at 100 yards. 36 inches at 1,000 yards. There is no rounding and no variant standard, which is the single strongest practical argument for the unit.
- 1 MOA = 1.047in at 100yd = 2.66cm at 100m (near enough 2.9cm at 100yd)
- 1 MIL = 3.6in at 100yd = 10cm at 100m
- 1 MIL = 3.438 MOA, so a 0.1 mil click is a bit larger than a 1/4 MOA click and a bit smaller than a 3/8
- IPHY / Shooter's MOA = exactly 1.000in at 100yd, roughly 4.5 percent finer than true MOA
- Neither unit is metric or imperial by nature — mils are used with inches constantly and it works fine
That 3.438 conversion is worth memorising because it is the one you will need under pressure. A 2 MOA dot is 0.58 mil. A 3 MOA dot is 0.87 mil. Six MOA is 1.75 mil. If somebody hands you a mil reticle and quotes a dot in MOA, that is the sum you do.
Click values in inches and centimetres
The four turret types you will meet, resolved at every range you are likely to zero or correct at. Multiply by the number of clicks.
Range (yd) 1/4 MOA (in) 1/4 MOA (cm) 1/8 MOA (in) 1/8 MOA (cm) 0.1 MIL (in) 0.1 MIL (cm) 0.05 MIL (in) 0.05 MIL (cm) 25 0.065 0.17 0.033 0.08 0.090 0.23 0.045 0.11 50 0.131 0.33 0.065 0.17 0.180 0.46 0.090 0.23 100 0.262 0.66 0.131 0.33 0.360 0.91 0.180 0.46 200 0.523 1.33 0.262 0.66 0.720 1.83 0.360 0.91 300 0.785 1.99 0.393 1.00 1.080 2.74 0.540 1.37 400 1.047 2.66 0.523 1.33 1.440 3.66 0.720 1.83 500 1.309 3.32 0.654 1.66 1.800 4.57 0.900 2.29 600 1.571 3.99 0.785 1.99 2.160 5.49 1.080 2.74 800 2.094 5.32 1.047 2.66 2.880 7.32 1.440 3.66 1,000 2.618 6.65 1.309 3.32 3.600 9.14 1.800 4.57 Use this to sanity-check a correction before you turn the dial. If the answer comes out over about 40 clicks, you have made an arithmetic error or you are zeroing a scope that needs a canted base. The row that surprises people is 25 yards. A 1/4 MOA click moves impact 0.065 inches — less than a sixteenth of an inch. If you are trying to fine-tune a zero on a 25-yard indoor range, you are asking the turret to do something you cannot see, and you will chase the group around for an hour. Zero at 25 to get on paper, then move out to at least 50 to actually finish.
Turning a measured miss into clicks
Measure the distance from the centre of your group to the centre of the bull, in inches. Then divide by the click value for your range. The table pre-solves the common cases so you can do it at the bench with cold hands.
Miss At range 1/4 MOA clicks 1/8 MOA clicks 0.1 MIL clicks 0.05 MIL clicks 1in 25 yd 15 31 11 22 1in 50 yd 8 15 6 11 1in 100 yd 4 8 3 6 2in 100 yd 8 15 6 11 3in 100 yd 11 23 8 17 4in 200 yd 8 15 6 11 6in 300 yd 8 15 6 11 8in 400 yd 8 15 6 11 12in 500 yd 9 18 7 13 24in 600 yd 15 31 11 22 Round to the nearest whole click and shoot a confirming group before touching the dial again. The formula behind every row: clicks = miss in inches divided by (click value at 100yd multiplied by range in hundreds of yards). Four rows in that table give the same answer — 8, 15, 6, 11 — because a 2in miss at 100, a 4in at 200, a 6in at 300 and an 8in at 400 are all the same angle. That is the whole point of angular units and it is worth internalising, because it means your correction is range-independent the moment you express the miss in MOA or mils rather than inches.
Which is the argument for mil reticles with mil turrets. Measure the miss with the reticle, read it off in mils, dial that number in mils. No inches, no range, no arithmetic. The scope does the conversion by existing.
What a dot actually covers
Red dot size is quoted in MOA, which means the same 2 MOA dot is a fine aiming point at 10 yards and a blindfold at 300. Here is the number in inches.
Dot size 10 yd 25 yd 50 yd 100 yd 150 yd 200 yd 1 MOA 0.10in 0.26in 0.52in 1.05in 1.57in 2.09in 2 MOA 0.21in 0.52in 1.05in 2.09in 3.14in 4.19in 3 MOA 0.31in 0.79in 1.57in 3.14in 4.71in 6.28in 4 MOA 0.42in 1.05in 2.09in 4.19in 6.28in 8.38in 6 MOA 0.63in 1.57in 3.14in 6.28in 9.42in 12.57in 8 MOA 0.84in 2.09in 4.19in 8.38in 12.57in 16.75in Compare the figure at your longest realistic distance against the target you must hit. If the dot is more than about a third of the target's width, you are guessing where the middle is. A 6 MOA dot on a pistol at 15 yards covers 0.94 inches. That is fine and it is why big dots feel fast — the eye finds a bright blob instantly. The same 6 MOA dot at 100 yards covers 6.28 inches, which is wider than a lot of the things people shoot at. Speed and precision are not a matter of preference here; they are a matter of what distance you actually shoot at, and the honest answer for most defensive pistol use is under 25 yards, where dot size barely matters.
The range where the dot eats the plate
The cleanest way to pick a dot size is to work out where it grows to equal the target. Past that range you are aiming at something you cannot see.
Dot size Covers a 6in plate at Covers an 8in plate at Covers a 10in plate at Practical precision ceiling 1 MOA 573 yd 764 yd 955 yd Anything you can range 2 MOA 287 yd 382 yd 478 yd Comfortable to ~250 yd 3 MOA 191 yd 255 yd 318 yd Comfortable to ~150 yd 4 MOA 143 yd 191 yd 239 yd Comfortable to ~100 yd 6 MOA 96 yd 127 yd 159 yd Comfortable to ~60 yd 8 MOA 72 yd 96 yd 119 yd Comfortable to ~40 yd The last column is the range at which the dot covers roughly a third of a 6in target — a workable rule for where a dot stops helping and starts hiding. Pick the largest dot whose ceiling clears your longest shot. There is a real trade here and it is not marketing. Big dots are found faster by the eye, particularly under stress, particularly with astigmatism, and particularly when the gun is not yet aligned. Small dots let you place a shot. The 2 MOA dot has become the default on rifles for the obvious reason that it clears a 6in plate to 287 yards, which is further than almost anyone shoots a red dot rifle.
On a pistol, take the big dot. The 6 MOA and 8 MOA options are not compromises at pistol distances; they are the correct choice, and the people running 1 MOA dots on carry guns are optimising for a range band they will never use.
Pick one unit and stop
Blunt opinion, since this is the question underneath the search: buy mils if you shoot with other people, buy MOA if you already own MOA glass and think in inches.
Mils win on three counts. The unit is exact rather than rounded. Spotter corrections are given in mils at every match and every training course in the country, so a mil scope lets you act on what you are told without converting. And 0.1 mil clicks are a sane resolution — fine enough to zero, coarse enough that a full-value wind correction is a handful of clicks rather than twenty.
MOA wins on one count, and it is not nothing: 1/4 MOA is a finer click than 0.1 mil, which some benchrest and varmint shooters genuinely want. If that is your discipline, keep MOA. If you cannot name a reason you need 0.26in resolution at 100 yards, you do not need it.
The one mistake that actually breaks things
Mixing units inside one scope. A mil reticle with MOA turrets is still sold, still bought, and still ruins afternoons. You measure a miss as 0.8 mil in the reticle, then dial 0.8 of something else on the turret, and the correction lands 30 percent short. Repeat twice and you have walked the group off the paper and concluded the scope is broken.
Check yours right now. Look at the turret cap: it will say MOA, MRAD or 0.1 MIL. Then look at the reticle spec on the maker's page. If they disagree, either sell it or write the 3.438 conversion on a strip of tape and stick it on the turret housing. There is no third option that ends well.
The other one is subtler. Some scopes have a mil reticle in the first focal plane and mil turrets, which is correct, but the reticle only subtends properly at a stated magnification if it is second focal plane. Second-plane reticles are honest at one power setting and lying at every other. That number is in the manual and it is usually maximum magnification. Find it, remember it, and do your ranging there.