In order to qualify to pay Zakat, you must first meet the mimimum Zakat nisab (threshold). Your expendable wealth should be at least the value of 87.48 grams of gold or 612.36 grams of silver, and your wealth should have remained above the nisab value for one Islamic (lunar) year, referred to as Hawl. Many Muslims opt to pay their Zakat during the Blessed month of Ramadan, but Zakat can be paid at any time of the year.
As the value of gold and silver constantly change, so too does the value of nisab. This is why we showcase the live nisab value on our Zakat calculator (via e-nisab.com).