Calculate arrow drop over distance with air resistance simulation. Essential for multi-pin setup and long-range accuracy.
Provide four numbers: arrow speed in fps from a chronograph, total arrow weight in grains, shaft diameter in millimeters, and the distance at which your sight is zeroed. The chart then plots how many inches the arrow sits above or below your line of sight at each yard out to 60 yards.
This is a true ballistic simulation, not a parabola formula. The flight is integrated numerically in 1-millisecond steps with aerodynamic drag (coefficient 1.5, representative of a fletched carbon arrow), air density of 1.225 kg/m³, and standard gravity of 9.80665 m/s². The launch angle is solved by bisection so the arc crosses your line of sight exactly at the zero distance you entered.
Read the curve relative to your zero: the value is 0 at the sight-in distance, and beyond it the drop steepens with every yard because the arrow is simultaneously losing speed to drag and spending more time falling per yard traveled. Comparing two arrow weights at the same zero quickly shows the flatness trade-off.
A parabola ignores air resistance. This calculator integrates the flight in 1-millisecond steps with a drag coefficient of 1.5 — typical for a fletched carbon arrow — so the predicted drop steepens realistically as the arrow sheds speed downrange instead of staying symmetric.
It defines your zero. The calculator solves the launch angle by bisection so the arrow's arc crosses the line of sight exactly at that distance, then reports every other drop value relative to that zero line.
Gravity pulls all arrows equally, but drag decelerates a light arrow more than a heavy one of the same diameter because drag acceleration is force divided by mass. A heavier arrow arrives slower off the bow yet loses a smaller fraction of its speed, which changes where it sits relative to your zero at long range.