What Is Transaction Hash (TxID)?
Also known as: TxID, Tx Hash, Transaction ID, TXID
In short
A transaction hash (TxID) is the identifier, made up of letters and numbers and produced from a blockchain transaction's data by a hash function, that uniquely identifies that transaction on the network.
When a transaction is created, the transaction data, which includes information such as the sender, recipient, amount, and signature, is passed through a specific hash function. On Bitcoin, SHA-256 is applied twice to the transaction data; on Ethereum, the Keccak-256 digest of the signed transaction is taken. The result is, on both networks, a 64-character hexadecimal string; on Ethereum, “0x” is prepended. The smallest change in the transaction data produces a completely different hash.
The TxID is the most practical way to track the status of a transfer. By pasting this value into a block explorer, the user can see whether the transaction has been confirmed, which block it is in, the fee paid, and the number of confirmations. Crypto exchanges and support teams also generally ask for the transaction hash when investigating a delayed or missing transfer.
A transaction hash is public information and sharing it does not put funds at risk; however, it can reduce privacy by making the related addresses and transaction history visible. It should not be confused with a private key or recovery phrase. On Bitcoin, before SegWit, the ability to change the TxID by altering signature data (transaction malleability) was a problem; SegWit fixed this problem.
Last updated: · This content is for information purposes only and is not investment advice.