Is Zakat Obligatory on Cryptocurrency?

Short answer: Yes. Cryptocurrency functions as a medium of exchange and a store of value, so it takes the ruling of currency/trade wealth. When its market value reaches the nisab and a lunar year (hawl) passes, 2.5% zakat is due on the total value. Allah commands taking sadaqah 'from their wealth' in general terms (Quran 9:103), and the Prophet ﷺ fixed one-fortieth (2.5%) on silver currency in Abu Bakr's zakat letter (Sahih al-Bukhari 1454). Crypto is simply a modern form of valuable, exchangeable wealth. Some scholars caution about the permissibility of trading crypto itself; that separate discussion does not lift the zakat obligation from wealth one actually owns. Evidence: Quran 9:103; Sahih al-Bukhari 1454; Ibn Majah 1792 (graded sahih by al-Albani) on the hawl condition; the principle applied by Shaykh Ibn Baz and Shaykh al-Uthaymin that modern currencies take the ruling of gold and silver. Application: On your zakat date, value all coins across wallets/exchanges in your local currency; if this (alone or combined with your other monetary wealth) reaches the nisab — the value of 87.48 g gold or 612.36 g silver — pay 2.5%. For complex individual cases, consult a qualified scholar.