Nitride-based light-emitting diodes (LEDs) with different electrode layouts were fabricated and analyzed. The turn-on voltage (V f) was proved to be highly related to the layout design of N-extending electrode. In addition, the electroluminescence intensity was almost proportional to the area of transparent contact layer (A TCL) subtracting the area of P-extending electrode (A P). Moreover, the current spreading was highly sensitive to the location and route of P- and N-extending electrodes. Good location and route can avoid thermal effect and damage. Finally, this paper proposed an easy and direct concept to estimate and predict the performance of nitride-based LEDs in turn-on voltage, electroluminescence intensity, and current spreading. It was highly potential to improve and change the currently mask design of nitride-based LEDs.