In Japanese homes, this appliance is a "Must Have". The photo shows the simplest version, costing less than 2021 US $20, but there are computer controlled versions selling for up to $300, or even more. Be Aware!, these are always sold by cup measure, but using a cup much smaller than our cup - See Buying.
This photo example is the simplest, but is adequate for most American home kitchens. I did have to add a cord switch so it could be turned off without pulling the plug. In China, Korea, or Japan, it might never be turned off - always either cooking rice or keeping it warm.
More expensive units have special programs for white rice, brown rice, mixed grains, porridge, stews and slow cooking. My needs are much more simple, and I only pull out a rice cooker for parties (I like the glass top for that), or for making a batch of rice for fried rice recipes. My daily rice is 1/4 cup (raw) cooked on the stovetop, way too little for a rice cooker.
The basic operating principle is simple. When the rice has absorbed all the water, the temperature in the bottom of the pan starts to rise. At a set temperature, the cooker switches from "cook" to "keep warm" - except my antique Hitachi - it turns off, but you have to push the "keep warm" toggle by hand.
What this all means is that you need to know your rice and how much water it needs. Be aware, most ratings are by one cup of rice. For two cups of rice you need a little less water per cup, and even less for 3 cups. Be aware: the ratios on our Rice pages are per American standard cup, not Japanese rice cup.
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