The circular synthetic jet (SJ) for different dimensionless stroke lengths and at Reynolds number Re=5000 was investigated in this paper. Particle image velocimetry was used. The flow was measured at a distance of 240 mm from the orifice and this area was divided into two fields of view (FOV). The parameter fields were created by the injunction of these two FOVs. The time-averaged velocity, turbulent kinetic energy (TKE), turbulence intensity, vorticity field, centreline, and profiles of SJ were presented and discussed. Additionally, the jet half-width of SJ was investigated. The data discontinuity at a line of the FOVs was discussed. The impact of the dimensionless stroke lengths on the parameters of SJ at Re=5000 was discussed.