The effects of ring radius and coupling spacing on the free spectral range (FSR), full width at half maximum (FWHM), quality factor, and sensitivity of single-channel and add–drop channel slot ring resonators were systematically investigated using FIMMPROP and PICWAVE numerical software. The single-channel ring resonator exhibited better characteristics, namely, a wider FSR and narrower FWHM compared with the add–drop structure; thus, it was evaluated to be more suitable for biochemical sensors. The FSR, FWHM, quality factor, and sensitivity for a single channel ring resonator with a radius of 59.4 µm and coupling gap of 0.5 µm were 2.4 nm, 0.087 nm, 17677, and 550 [nm/RIU], respectively.