Group Size Calculator

Annotate a target photo to measure group size, mean radius, and correction.

Display units
Setup
Required for MOA values
Real-world length of the line you'll draw
Draws bullet holes at correct scale
Annotation
Legend
Reference line
POA — Point of Aim
POI — Bullet holes
Group centroid

Drop your target photo here

or click to browse — JPEG, PNG, WebP

Results

Draw a reference line on the image.

Shots (POIs) —
Group size (ES) —
Mean radius —
Group offset from POA —
Correction needed —

Enter the distance above to see MOA values.