Rice-to-Water Ratio & Cook Time Calculator
Plug in your grain, amount, cooker and altitude. Get the exact water to add — shown in both the 180ml rice cooker cup and the 240ml US cup, because using the wrong cup is the #1 cause of bad rice.
Water to add
Enter an amount greater than zero to see your water and cook time.
- Estimated cook time
- ~35 min
- Base ratio (rice : water)
- 1 : 1.5
- Dry rice
- 360 ml
- Cooker adjustment
- None
- Altitude adjustment
- None
Every ratio, cook time and adjustment above comes straight from our own Master Rice to Water Ratio Chart, high-altitude guide, and serving-size guide (1/2 cup dry rice per adult serving). These are guide values — your rice, cooker markings and taste are the final word.
Why show water in two different cups?
Most rice cookers ship with a measuring cup that holds 180ml (a Japanese go), not the standard US cup of 240ml. Following a ratio with the wrong cup is the single biggest reason rice turns out mushy or crunchy. Rather than guess which cup you have, this calculator works out the actual water volume and shows it both ways plus in millilitres — so whatever cup is in your drawer, you can measure it correctly.
How the numbers are calculated
- Base ratio & cook time come from the grain you pick in our published ratio chart.
- Amount is converted to a dry volume (180ml or 240ml per cup, or 1/2 US cup of dry rice per serving).
- Cooker type shifts water: IH cookers use about 5–10% less, pressure cookers 10–15% less; basic and fuzzy-logic cookers use the standard ratio.
- Altitude adds water and time above 3,000 ft (+5% to +15% water, +5 to +12 minutes) because water boils cooler up high.
Want the full explanation and the complete chart? Read the Ultimate Rice Cooker Water Ratio Chart, learn how much rice to cook per person, and see the high-altitude cooking guide. New to rice cookers? Start with how to use a rice cooker.