Do Rice Cookers Turn Off Automatically?

Yes - it's the whole point of a rice cooker

Every rice cooker turns its cooking cycle off automatically— you do not have to watch it, and it will not boil dry or burn the way an unattended pot on the stove would. That automatic shut-off is the entire reason the appliance exists: set it and walk away. What differs between a $25 cooker and a $200 one is not whether it stops, but how gracefully it manages the heat and what it does afterward.

How it knows the rice is done

The mechanism is simple and clever. While there is water in the pot, the contents stay at boiling point, about 212°F, no matter how much heat the element adds — the water absorbs it. Once the rice has soaked up all the water, the pot's temperature climbs past 212°F, and a temperature sensor (in a basic cooker, a spring-loaded magnetic thermostat) detects that rise and trips the cooker out of Cook mode. No timer, no guesswork — it is reacting to the actual state of the rice, which is why it works regardless of how much rice you put in. There is more on this in how long a rice cooker takes.

The three types, and what happens after shut-off

What the cooker does after the cook cycle ends is where the types diverge:

• Basic on/off cookers simply switch off (the button pops up) and stop heating. The rice starts to cool right away, so eat it fairly soon.
• Keep Warm cookers shut the cook cycle off and then drop to a low Keep Warmholding temperature that keeps the rice hot and safe to eat for hours — covered in is it safe to leave rice on Keep Warm.
• Fuzzy-logic (Micom) cookers like the Zojirushi Neuro Fuzzy go further: a microchip adjusts the heat throughout the cook, then holds and even re-warms on Keep Warm. That is what fuzzy logic buys you.