Sight Tape Calculator

The current calculation estimates drop purely from a simplified physics trajectory based on arrow speed and distance, and doesn't yet blend in the pin gap measurements you can enter as a calibration correction against your bow's real, physically confirmed sight settings. Those measurements are captured for your own reference alongside the calculated estimate, but the two aren't currently combined into one calibrated result.

Under this trajectory model, drop scales with the square of distance, so tripling the distance from 20 to 60 yards doesn't triple the drop — it multiplies it roughly ninefold, all else equal, which is why the gap between consecutive sight pins keeps widening at longer distances rather than staying evenly spaced. This is a fundamental property of projectile motion under gravity, not specific to any particular bow or arrow setup.

Drop scales inversely with the square of velocity in this model, meaning a relatively modest increase in arrow speed produces an outsized reduction in drop, especially at longer distances where the arrow spends more total time in flight for gravity to act on. This is exactly why archers chase faster bow setups partly for a flatter trajectory, not just for more kinetic energy on impact.

Treat them as a solid starting estimate rather than a finished, ready-to-shoot sight tape — real arrow flight is affected by fletching drag, wind, arrow flex, and individual bow tuning quirks that a simplified point-mass trajectory doesn't model, and even chronographed arrow speed can vary shot to shot. Confirming and fine-tuning each pin's actual position by shooting groups at each real distance is the standard, reliable way archers finalize a sight tape.