The rice water ratio in a rice cooker is the proportion of water to rice used when cooking rice in a rice cooker. The ideal ratio varies depending on the type of rice being cooked and the desired texture of the cooked rice. For example, a 1:1 ratio of water to rice will produce a relatively dry and fluffy rice, while a 1:2 ratio will produce a more moist and sticky rice.
Getting the rice water ratio correct is important for achieving the desired texture of cooked rice. Too little water can result in undercooked rice that is hard and chewy, while too much water can result in overcooked rice that is mushy and sticky.