Home
»
Glossary
»
UTXO (Unspent Transaction Output)

UTXO (Unspent Transaction Output)

UTXO, short for “Unspent Transaction Output,” is a core concept in blockchain technology. In a blockchain, a UTXO represents a specific amount of cryptocurrency that has been assigned to a particular address and has not yet been spent. When a cryptocurrency transaction occurs, the funds being sent are essentially the unspent UTXOs of the sender, and the recipient is assigned a new UTXO with the value of the transaction.

To understand UTXOs better, let’s consider how a typical transaction works in a blockchain. When a user wants to send some cryptocurrency, they create a transaction that specifies the recipient’s address and the amount to be sent. The transaction then goes through a process called mining, where it is verified and added to the blockchain. 

In the process, the blockchain network verifies that the sender has sufficient unspent UTXOs to cover the transaction amount, and then marks those UTXOs as “spent.” The remaining unspent UTXOs, if any, are returned to the sender as “change” in a new UTXO.

This system of UTXOs ensures that there is no double-spending of cryptocurrency, as each UTXO can only be used once in a transaction. It also provides a level of anonymity for users, as UTXOs are not tied to specific user accounts but rather to unique addresses. 

UTXOs can also be used for more complex transactions, such as multi-signature transactions, where multiple parties must sign off on a transaction before it can be completed. Overall, UTXOs are a fundamental building block of blockchain technology and enable the secure and decentralized transfer of cryptocurrency. 

Understanding UTXOs is essential for anyone interested in blockchain development, as they are a critical part of designing and implementing secure and efficient blockchain systems.