Nisaab [Minimum Threshold] (Hadith No. 1186)

Narrated Abu Said:
Allah's Apostle (p.b.u.h) said, "No Zakat is due on property mounting to less than five Uqiyas (of silver), and no Zakat is due on less than five camels, and there is no Zakat on less than five Wasqs." (1 Wasq = 60 Sa's) & (1 Sa' = 3 kg app.)
In Sharia (Islamic Law) niṣāb (نِصاب) is the amount one's net worth must exceed for the Muslim owner to be obligated to give zakat. Several hadith have formulas for calculating niṣāb, the most prominent of which declaring that No Zakāt is due on wealth until one year passes. Zakat is then determined based on the amount of wealth acquired; the greater the assets, the greater the tax. It is not subject to special exemptions. [Wikipedia]
Nisaab for naqd = gold: 7.5 tolas (85 grams), silver: 595 grams
Nisaab for paper money = whatever amount reaches the nisaab for naqd
Nisaab for livestock = camel: 5, cattle: 30, sheep: 40
Nisaab for agricultural produce: 5 wasqs (60 Sa`s) of dates, grapes, and grains such as corn, barley, rice etc.
Bear in mind that these quantities only determine eligibility/obligation of payment of Zakah. Rate of Zakah is not under discussion, yet.