How precisely is Zakat calculated on money, gold, and real estate?

The nisab (minimum threshold) for zakat on money is determined by comparing it to the nisab of gold or silver, whichever is more beneficial to the poor. The nisab for gold is 85 grams, and for silver, it is 595 grams. If the value of the money reaches the nisab of either of these, zakat becomes obligatory, and its amount is one-quarter of one-tenth (2.5%). Real estate intended for trade is subject to zakat as trade goods, based on its market value at the time the hawl (one lunar year) is completed. As for rented real estate, its income is subject to zakat if it reaches the nisab and a hawl has passed over it. There is no zakat on non-commercial or non-rented real estate.