What is the approximate length of the driven element of a Yagi antenna?

The driven element of a standard Yagi-Uda antenna is typically a center-fed half-wave dipole. Therefore, its physical length is approximately 1/2 of a wavelength at the antenna's design frequency. While parasitic elements (directors and reflectors) are also close to this length, the driven element itself is specifically cut to match a 1/2 wavelength resonance. Quarter-wave (1/4) elements are typically used for vertical ground-plane antennas, and full-wavelength elements are characteristic of loop or quad antennas.