sat/vB
sat/vB means satoshis per virtual byte and is a common unit for expressing the fee rate of a Bitcoin transaction.
✦ Key Insight
Choosing an appropriate sat/vB rate affects how much a transaction costs and how competitive it is for block space.
✕ Common Misconceptions
Do not confuse total transaction fee with fee rate. Two transactions using the same sat/vB can still pay different total fees if their sizes differ.
Detailed Explanation
In Practice
Dig Deeper
Mempool
A mempool is a node's temporary pool of valid, unconfirmed transactions waiting to be included in a block.
Child pays for parent (CPFP)
Child pays for parent is a Bitcoin fee-bumping technique where a high-fee child transaction incentivizes miners to confirm it together with its low-fee unconfirmed parent.
UTXO
A UTXO is an unspent transaction output that represents a discrete amount of cryptocurrency available to be used as an input in a future transaction.
Replace by fee (RBF)
Replace by fee is a Bitcoin transaction replacement mechanism that can allow an unconfirmed transaction to be replaced by another version offering a higher fee.