Determine your optimal zero distance and maximum point-blank range for hunting and target archery.
Enter your arrow's speed, total weight, and shaft diameter, plus an acceptable target radius in inches — the vertical tolerance you are willing to accept above or below your exact aim point.
The tool sweeps candidate zero distances from 10 to 80 yards in 1-yard steps. For each candidate it runs a full drag-based trajectory (drag coefficient 1.5) and measures the farthest distance at which the arrow never strays outside your chosen radius. It then reports the zero that maximizes this window — your maximum point-blank range (MPBR).
Three results come back: the optimal zero distance, the maximum point-blank range itself, and the holdover in inches at 60 yards. Inside the MPBR you can hold dead-center without thinking about drop; the 60-yard holdover figure tells you how much correction a shot beyond that window demands.
It is the farthest distance at which you can hold dead-center and the arrow still stays within your chosen tolerance radius above or below the line of sight for the entire flight. Inside that range you never need to hold over or under.
It tests every candidate zero from 10 to 80 yards in 1-yard steps, runs a full drag-based trajectory for each, and keeps the zero whose within-tolerance window reaches farthest. That winner is reported together with the resulting maximum point-blank range.
For shots beyond your point-blank window, it reports how many inches the arrow sits below the zero line at 60 yards on the simulated trajectory — a concrete gauge of how much correction a long shot with your setup demands.