Exact water amounts by cooking method.
The Instant Pot needs slightly less water (0.1 cup less per cup of rice) because there's no evaporation under pressure. Rice cookers use roughly the same ratio as stovetop. The finger method (popular in Asian cooking): place rice in pot, add water, touch the tip of your finger to the rice surface — water should reach the first knuckle (~1 inch above the rice). This works for any quantity because the water-above-rice depth stays constant. Pro tip for fluffy white rice: rinse 3-4 times until water is clear (removes surface starch that causes clumping), soak 30 minutes, then cook with slightly less water. For brown rice, soaking 1+ hours reduces cooking time by 25%.