Zakat should be paid if an individual's monetary savings reaches at least the silver nisab and a whole lunar (hijri) year has passed. 2.5% from the total amount equal to and above the nisab should be paid in zakat.
Example for gold:
If the price of gold per gram in the UK is £10. The Nisab for gold would be £10 x 85( grams of gold). If a person's savings reaches this amount and more (£850+), whilst a whole lunar year has passed, they must pay 2.5% from this. In this case the zakat to pay would be £21.25
Example for silver:
If the price of silver per gram in the UK is £1. The Nisab for silver would be £1 x 595( grams of silver). If a person's savings reaches this amount and more (£595+), whilst a whole lunar year has passed, they must pay 2.5% from this. In this case the zakat to pay would be £14.87
This calculator focuses on monetary savings, for zakat concerning livestock, properties etc scholarly advice should be sought.