In this paper, we propose the design of a high definition multimedia interface (HDMI) 2.1 connector considering signal integrity (SI) for improved electrical characteristics. We design the receptacle based on the analysis of electrical specification margins for 4 channels: D0, D1, D2, CK. The electrical characteristic includes insertion loss (IL), attenuation to crosstalk noise ratio (ACR) and time-domain reflectometry (TDR) impedance. Customized solutions for each channel are investigated considering their electrical performance margins respectively. As a result, we verify the SI performance improvement compared to the previous work through the 3D electromagnetic (EM) simulation.