Ferroelectric fibers based on a commercial lead zirconium titanate powder were investigated by a new characterization method to measure single fiber properties, such as large signal polarization and longitudinal free strain, and small signal properties, such as piezoelectric constant. To verify the measurements, the free strain data were compared with dynamic mechanical analyzer measurements. For this investigation, lead zirconate titanate fibers were sintered in lead-rich atmosphere at different temperatures. Microstructure and phase composition were analyzed by scanning electron microscope and X-ray diffraction. By increasing the temperature from 1150°C to 1200°C, the electromechanical behavior of the fibers could be improved: an increase in remnant and saturation polarization occurred. A d₃₃ as of ∼430 and ∼400 pm/V could be measured for 1150°C and 1200°C, respectively. These d₃₃ values are very close to the one reported on the data sheet of the material.