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Z-cash is a decentralized and open-source cryptocurrency that provides strong privacy protections. Shielded transactions hide the sender, recipient, and value on the blockchain. If Bitcoin is like http for money, Zcash is httpsa secure transport layer. Bitcoin is the first digital currency to see widespread adoption. Although payments are conducted between pseudonyms, Bitcoin cannot offer strong privacy guarantees: payment transactions are recorded in a public decentralized ledger, from which much information can be deduced. Zerocoin (Miers et al., IEEE S&P 2013) tackles some of these privacy issues by unlinking transactions from the payments origin. Yet it still reveals payment destinations and amounts, and is limited in functionality. Our results leverage recent advances in zero-knowledge Succinct Non-interactive ARguments of Knowledge (zk-SNARKs). We formulate and construct decentralized anonymous payment schemes (DAP schemes). A DAP scheme lets users pay each other directly and privately: the corresponding transaction hides the payments origin, destination, and amount. We provide formal definitions and proofs of the constructions security. We then build Zerocash, a practical instantiation of our DAP scheme construction. In Zerocash, transactions are less than 1 kB and take under 6 ms to verify orders of magnitude more efficient than the less-anonymous Zerocoin and competitive with plain Bitcoin.