What is TXID?
A TXID, or transaction ID, is a unique identifier for a blockchain transaction, created by hashing the transaction data. You use it to look up a transfer on a block explorer and to prove a payment was sent.
On this page 6
A TXID (transaction ID) is a unique identifier for a blockchain transaction, created by hashing the transaction’s data. It usually appears as a 64-character string of letters and numbers. Think of it as a parcel tracking number: with the TXID you can find your transfer on a block explorer, check its status and share proof of payment with an exchange or recipient.
How is a TXID created?
On Bitcoin, the TXID is produced by running the transaction data through SHA-256 twice. Change a single detail in the transaction and you get a completely different TXID. On Ethereum and other EVM chains, the same concept is usually called the “transaction hash” or “Tx Hash” and starts with “0x”.
The format varies by network:
- Bitcoin: a 64-character hexadecimal string.
- Ethereum, BNB Chain, Arbitrum: 66 characters starting with “0x”.
- Solana: a longer alphanumeric transaction signature.
How do you find and look up a TXID?
- In your wallet: open the transaction in your history. The details show the TXID or a “view on explorer” link.
- On an exchange: the withdrawal history shows the TXID once the exchange has broadcast the transaction. An internal request or reference number is not the same thing.
- On a block explorer: paste the TXID into the explorer for the right network, such as mempool.space for Bitcoin, Etherscan for Ethereum or Tronscan for TRON.
The explorer shows whether the transaction is pending or included in a block, how many confirmations it has, the sending and receiving addresses, the amount and the fee paid. Our guide on tracking a blockchain transaction walks through it step by step.
What if the explorer can’t find your TXID?
The most common reason is searching on the wrong network’s explorer: USDT sent over TRON won’t show up on Etherscan. If you’re on the right explorer, the transaction may not have propagated yet or may have dropped out of nodes’ mempools. With exchange withdrawals, the platform may simply not have broadcast it yet.
Don’t send the same amount again to resolve the uncertainty. If the first transaction eventually confirms, you’ll have paid twice. Check the status on the sending platform first and, if needed, contact support with the TXID.
If the explorer shows the transaction as confirmed but your exchange balance hasn’t updated, check whether the exchange’s required number of confirmations has been reached. If it has, the usual culprits are a wrong network, a missing memo or tag, or a token the exchange doesn’t support. In every case, the TXID is the key piece of information support will need.
Is it safe to share a TXID?
A TXID is not a private key or password; nobody can spend your funds with it, and exchange support teams routinely ask for it when tracing missing deposits. But blockchain records are public, so sharing a TXID alongside your identity links you to the addresses and payment history involved. Share it only where it’s needed.
For smart contract transactions, a “Success” status does not by itself prove the token movement you expected happened. Check the separate “Token Transfers” section on the explorer as well.
Frequently asked questions
Is a TXID the same as a transaction hash?
Yes, in practice. The TXID is the hash of the transaction data, and Ethereum explorers simply label it “Transaction Hash.”
Can a TXID change?
Not once a transaction is confirmed. Before SegWit, Bitcoin had a flaw called transaction malleability that let third parties alter an unconfirmed transaction’s TXID by tweaking its signature. SegWit largely fixed it.
Can one TXID contain several transfers?
Yes. Exchanges often batch payouts to dozens of users into a single Bitcoin transaction, so look for your own address and amount among the outputs.