Idli Dosa Batter Calculator
Calculate the perfect rice-to-urad dal ratio scaled to any quantity.
Fermentation guide for Indian climate
Fermentation is the most important step — it makes idlis soft and gives dosas their tangy flavour. Time varies greatly by season.
Batter ferments very quickly — 6–8 hours is often enough. Watch carefully and refrigerate as soon as it rises and smells tangy. Over-fermented batter is very sour and makes flat idlis.
Fermentation needs help. Keep the batter inside a slightly warm oven (just turn on the light), in a warm corner, or wrap the vessel in a thick cloth. Allow 12–16 hours.
Volume roughly doubles. The top is domed with small bubbles. Smells pleasantly tangy (not sour or alcoholic). Batter should be thick enough to coat the back of a spoon.
Soaking and grinding tips
Frequently asked questions
Why are my idlis not soft and fluffy?
The most common reasons: under-fermented batter (batter did not rise enough), urad dal was not ground finely enough (must be smooth and airy), too much water in the batter (should be thick), or over-steaming (10–12 minutes is ideal — check with a toothpick). Urad dal quality also matters — older dal ferments poorly.
What is the difference between idli and dosa batter?
The main difference is the rice-to-dal ratio. Idli batter uses 3:1 rice to urad dal (by volume) for a thicker, softer batter. Dosa batter uses 4:1 for a thinner, crispier result. Dosa batter also includes fenugreek seeds which aid fermentation and add a slight bitterness. Both use the same base process.
Can I use store-bought idli rice or regular rice?
Idli rice (parboiled short-grain rice) gives the best soft, white idlis with good fermentation. Regular raw rice (long-grain basmati) also works but produces denser idlis with a slightly different texture. Avoid fragrant rice varieties — they do not ferment as well.
How long does idli/dosa batter last in the fridge?
Refrigerated batter lasts 4–5 days. After day 3, the batter gets more sour — use it for uthappam or pesarattu. Always add salt only at the time of making, not before fermentation, as salt inhibits the fermentation process slightly.
Can I make dosa batter in a mixer-grinder instead of a wet grinder?
Yes, though wet grinders produce fluffier idlis because they incorporate more air into the dal. In a mixer, grind in short pulses with cold water to avoid overheating the motor. Keep the dal smooth and the rice slightly grainy. The batter works well, especially for dosa.