One MOA (minute of angle) covers 29.1 mm at 100 metres, which is 1.047 inches at 100 yards, and it scales in a straight line with distance: 7.3 mm at 25 m, 14.5 mm at 50 m and 58.2 mm at 200 m. Multiply that figure by your dot size or your click value and you know exactly how much target the dot covers and how far each turret click moves the point of impact.
The charts below are worked out from the exact definition rather than rounded rules of thumb. They lead with metres, which is how British ranges are laid out, and give yards alongside because that is how American manufacturers print their manuals. New to the term? Start with what MOA is, explained simply.
Key takeaways
- 1 MOA = 29.1 mm at 100 m = 1.047 in at 100 yd, and it doubles every time the distance doubles.
- A 1/4 MOA scope click moves impact 7.3 mm at 100 m, so it takes about 14 clicks to move 100 mm.
- A 0.1 MRAD click moves exactly 10 mm at 100 m, which is why metric shooters find mils easier to work with.
- A 2 MOA red dot covers 58 mm at 100 m; a 6 MOA dot covers 175 mm at the same distance.
- 100 m is 109.4 yd, about 9% further than 100 yd, so yard-based tables understate what you see at a metric range.
The formula behind every chart
MOA is an angle: one sixtieth of a degree. Because it is an angle, the size it covers grows with distance. Two conversions do all the work:
- Metric: size in mm = MOA × 0.291 × distance in metres.
- Imperial: size in inches = MOA × 1.047 × (distance in yards ÷ 100).
So a 3.25 MOA dot at 50 m covers 3.25 × 0.291 × 50 = 47 mm. A 1/4 MOA click at 200 m moves 0.25 × 0.291 × 200 = 14.5 mm. Every cell below is just that sum.
How much does your dot cover at distance?
This is the coverage in millimetres at metric distances, with the equivalent yardage in brackets. It applies to red dot sizes and to any MOA-sized reticle element, such as the centre dot of an illuminated scope.
| Dot or reticle size | 25 m (27 yd) | 50 m (55 yd) | 100 m (109 yd) | 200 m (219 yd) | 300 m (328 yd) |
|---|---|---|---|---|---|
| 1 MOA | 7 mm | 15 mm | 29 mm | 58 mm | 87 mm |
| 2 MOA | 15 mm | 29 mm | 58 mm | 116 mm | 175 mm |
| 3 MOA | 22 mm | 44 mm | 87 mm | 175 mm | 262 mm |
| 3.25 MOA | 24 mm | 47 mm | 95 mm | 189 mm | 284 mm |
| 6 MOA | 44 mm | 87 mm | 175 mm | 349 mm | 524 mm |
| 8 MOA | 58 mm | 116 mm | 233 mm | 465 mm | 698 mm |
The same coverage at round yard distances, in inches, for anyone working from an American manual or a yard-marked range:
| Dot or reticle size | 25 yd (23 m) | 50 yd (46 m) | 100 yd (91 m) | 200 yd (183 m) | 300 yd (274 m) |
|---|---|---|---|---|---|
| 1 MOA | 0.3 in | 0.5 in | 1.0 in | 2.1 in | 3.1 in |
| 2 MOA | 0.5 in | 1.0 in | 2.1 in | 4.2 in | 6.3 in |
| 3 MOA | 0.8 in | 1.6 in | 3.1 in | 6.3 in | 9.4 in |
| 3.25 MOA | 0.9 in | 1.7 in | 3.4 in | 6.8 in | 10.2 in |
| 6 MOA | 1.6 in | 3.1 in | 6.3 in | 12.6 in | 18.8 in |
| 8 MOA | 2.1 in | 4.2 in | 8.4 in | 16.8 in | 25.1 in |
Small dots (1 to 2 MOA) cover less of the target, which helps precision at 100 m and beyond. Large dots (6 to 8 MOA) are quicker to find up close but at 200 m a 6 MOA dot is 349 mm across, wider than the vital zone of a fox. The red dot size chart covers which size suits which job, and you can browse by dot size in our red dot sights.
Click values: how far does one click move?
Scopes mostly adjust in 1/4 MOA or 0.1 MRAD clicks. Many LPVOs use 1/2 MOA: the SIG Sauer TANGO-MSR 1-6x24 and the Burris RT-6 1-6x24 are both 1/2 MOA per click, according to their makers. Red dots usually use 1/2 or 1 MOA. Here is how far one click moves the point of impact at metric distances:
| Click value | 25 m (27 yd) | 50 m (55 yd) | 100 m (109 yd) | 200 m (219 yd) | 300 m (328 yd) |
|---|---|---|---|---|---|
| 1/4 MOA | 1.8 mm | 3.6 mm | 7.3 mm | 14.5 mm | 21.8 mm |
| 1/2 MOA | 3.6 mm | 7.3 mm | 14.5 mm | 29.1 mm | 43.6 mm |
| 1 MOA | 7.3 mm | 14.5 mm | 29.1 mm | 58.2 mm | 87.3 mm |
| 0.1 MRAD | 2.5 mm | 5.0 mm | 10.0 mm | 20.0 mm | 30.0 mm |
Read the other way round, this is how many clicks it takes to move the group 25 mm (about 1 inch) at metric distances:
| Click value | 25 m (27 yd) | 50 m (55 yd) | 100 m (109 yd) |
|---|---|---|---|
| 1/4 MOA | 13.8 clicks | 6.9 clicks | 3.4 clicks |
| 1/2 MOA | 6.9 clicks | 3.4 clicks | 1.7 clicks |
| 1 MOA | 3.4 clicks | 1.7 clicks | 0.9 clicks |
| 0.1 MRAD | 10 clicks | 5 clicks | 2.5 clicks |
And the clicks needed to move the group 1 inch at yard distances:
| Click value | 25 yd (23 m) | 50 yd (46 m) | 100 yd (91 m) |
|---|---|---|---|
| 1/4 MOA | 15.3 clicks | 7.6 clicks | 3.8 clicks |
| 1/2 MOA | 7.6 clicks | 3.8 clicks | 1.9 clicks |
| 1 MOA | 3.8 clicks | 1.9 clicks | 1 click |
| 0.1 MRAD | 11.1 clicks | 5.6 clicks | 2.8 clicks |
Worked examples
- Scope at 100 m, 1/4 MOA clicks, group 100 mm low: 100 ÷ 7.3 = 13.8, so dial 14 clicks up.
- Same correction on a 0.1 MRAD scope: 100 ÷ 10 = exactly 10 clicks.
- Red dot at 25 m, 1/2 MOA clicks, group 20 mm right: 20 ÷ 3.6 = 5.5, so dial 5 or 6 clicks left and confirm.
The trap is zeroing at short range: at 25 m a click moves impact a quarter of what it does at 100 m, so a correction that looks like two clicks is really eight. The full sequence is in our guide to zeroing a rifle scope.
Metres, yards and what 1 MOA and 1 MRAD cover
Range distances in Britain are nearly always in metres. This table converts them and shows both angular units at each distance:
| Metres | Yards | 1 MOA covers | 1 MRAD covers |
|---|---|---|---|
| 25 m | 27.3 yd | 7.3 mm (0.29 in) | 25 mm (1.0 in) |
| 50 m | 54.7 yd | 14.5 mm (0.57 in) | 50 mm (2.0 in) |
| 100 m | 109.4 yd | 29.1 mm (1.15 in) | 100 mm (3.9 in) |
| 200 m | 218.7 yd | 58.2 mm (2.29 in) | 200 mm (7.9 in) |
| 300 m | 328.1 yd | 87.3 mm (3.44 in) | 300 mm (11.8 in) |
The two numbers worth memorising are 1 MOA ≈ 29 mm at 100 m and 1 MRAD = 100 mm at 100 m. One MRAD is 3.44 MOA. The MRAD vs MOA guide explains which system suits which shooter.
UK note
Most UK ranges and zero distances are metric, while most turret caps, manuals and ballistic tables come from America in yards. A 100 m zero is 9.4 yards further than a 100 yd zero, so a click moves about 9% more at the metric distance. On a red dot at 25 m that difference is lost in the group, but when you are dialling a scope for 300 m it is the difference between a hit and a miss. Work in one system from start to finish.
Expert tip
Measure group offsets on the target in millimetres and divide by the per-click figure for that distance from the table above. It is quicker and more accurate than converting to inches and back, and it stops the classic mistake of using the 100 m figure at 50 m.
Frequently asked questions
Is 1 MOA exactly 1 inch at 100 yards?
No. It is 1.047 inches, about 5% more. At 100 m it is 29.1 mm. The one-inch shortcut is fine for a red dot but adds up when you dial a scope a long way.
How many 1/4 MOA clicks is 10 cm at 100 metres?
About 14. Each 1/4 MOA click moves 7.3 mm at 100 m, and 100 ÷ 7.3 = 13.8. On a 0.1 MRAD scope the same 10 cm is exactly 10 clicks.
What dot size should I choose?
A 2 MOA dot suits precise shooting at rifle distances. A 3 to 3.25 MOA dot is a good compromise, and 6 MOA suits fast pistol and close-range work. The coverage table shows what each one hides at your distances.
How do I convert a click value to millimetres at any distance?
Multiply the click value in MOA by 0.291, then by the distance in metres. A 1/2 MOA click at 50 m is 0.5 × 0.291 × 50 = 7.3 mm. For 0.1 MRAD, it is simply the distance in metres ÷ 10, in mm.
Shop this guide
- Red Dot Sights — compare dot sizes from 1 to 8 MOA.
- Rifle Scopes — MOA and MRAD scopes, with the click value in each listing.
- LPVO Rifle Scopes — 1-6x to 1-10x scopes, many with 1/2 MOA clicks.
