Yagi Element Spacing Calculator

About this calculator

A Yagi-Uda antenna gets its directional gain from a row of parallel elements — a driven element, one reflector behind it, and one or more directors in front — all tuned relative to the operating wavelength λ = c/f. Element spacing, not just length, is what determines how the elements' fields combine constructively in the forward direction.

Typical designs place the reflector about 0.15 to 0.25 λ behind the driven element and directors roughly 0.1 to 0.2 λ apart in front of it — closer director spacing generally raises gain but narrows bandwidth and increases design sensitivity, which is why real antenna designs are usually optimized numerically rather than built from spacing rules alone.

Amateur radio operators and antenna builders use this frequency-to-wavelength relationship as a starting point for laying out element positions before fine-tuning a design in modeling software or on the workbench.