Nisab is the minimum amount of wealth you must hold before Zakat becomes due. It is fixed in weight — 7.5 tola of gold, or 52.5 tola of silver — but its value in rupees moves with the market, which is why the threshold is different every year.
Why there are two thresholds
Both weights come from the same era, when their values were roughly equivalent. They no longer are. Silver has fallen a long way relative to gold, so the silver threshold today is a small fraction of the gold one.
The practical consequence is significant. Using the silver nisab, far more people are liable for Zakat — and far more reaches those who need it. Using the gold nisab, fewer people pay.
Which to choose
The majority position among scholars is to use silver, precisely because it is more generous to the poor. Some follow the gold threshold on the basis of their school or their scholar advice, and that is a legitimate position.
Our calculator lets you pick either, and shows both thresholds at the current rates so you can see the difference before you decide.