Rifle Scope Click Adjustment Calculator (MOA & MRAD)

Rifle scope adjustments are made by turning turrets that move the reticle in small increments. These increments are measured in MOA (Minute of Angle) or MRAD (Milliradians).

MOA, or Minute of Angle:

1 MOA = 1/60th of a degree of angle. At 100 yards, 1 MOA = 1.047 inches (commonly rounded to 1 inch for simplicity). At 200 yards, 1 MOA = ~2.094 inches. At 300 yards, ~3.14 inches. And so on.

Inches at distance = MOA × (distance in yards / 100) × 1.047

Most scopes have 1/4 MOA clicks, meaning each click moves point of impact 0.25 MOA. At 100 yards: 1 click = 0.262 inches. To move 1 inch at 100 yards you need 4 clicks.

MRAD (Milliradians / Mil):

1 MRAD = 1/1000 of a radian. At 100 meters, 1 MRAD = 10 cm (exactly, by definition). At 100 yards, 1 MRAD = 3.6 inches.

Centimeters at distance = MRAD × (distance in meters / 100) × 10

Most MRAD scopes have 0.1 MRAD clicks. At 100 meters: 1 click = 1 cm. Very intuitive for metric shooters.

Common click values:

How to calculate clicks needed:

1. Shoot a group and measure how far off center it is
2. Divide the offset by the click value at that distance
3. Round to the nearest whole click

Which way to turn

Dial toward where you want the bullet to go, not toward the hole in the paper. A group that landed low needs UP clicks. A group that landed left needs RIGHT clicks. Every turret is engraved with an arrow and a letter for this, and the letter tells you which way the impact moves.

Run the calculator once for the vertical error and once for the horizontal error. They use the same click value, so the two answers come from the same page.

Example (MOA scope): You’re shooting at 200 yards. Your group is 3 inches low and 1.5 inches right.

One click at 200 yards is 0.25 MOA × 2 × 1.047 = 0.5235 inches, which the calculator shows as 0.523".

• Vertical: 3 ÷ 0.5235 = 5.7, so 6 clicks UP
• Horizontal: 1.5 ÷ 0.5235 = 2.9, so 3 clicks LEFT (the group is right of centre, so move impact left)

Both round up, and the vertical one rounds a long way: six clicks moves 3.14", so you end up about 0.14" past centre. At 200 yards that is nothing, but on a 1/4 MOA scope it is the best you can do.

Tip: Shoot 3 to 5 round groups, not single shots, to average out shooter error. Measure from the centre of the group, not from the closest hole. Always confirm your zero with a follow-up group after adjustments, because a scope that has been sitting in a case sometimes needs a few rounds to settle before the adjustment holds.