Replace-by-Fee (RBF)
Replace-by-Fee is a Bitcoin mechanism that lets an unconfirmed transaction be replaced by a conflicting version that pays a higher fee.
✦ Key Insight
RBF gives senders a way to raise fees when a Bitcoin transaction is stuck because its original fee was too low.
✕ Common Misconceptions
RBF only applies before confirmation and depends on transaction and node policy. A replacement may also change outputs, so verify wallet prompts carefully.
Detailed Explanation
In Practice
Dig Deeper
Confirmation
A confirmation indicates that a transaction has been included in a block and has gained additional blockchain history after it.
Mempool
A mempool is a node's temporary pool of valid, unconfirmed transactions waiting to be included in a block.
Transaction
A blockchain transaction is a signed or authorized instruction that changes blockchain state or transfers value when accepted by the network.
sat/vB
sat/vB means satoshis per virtual byte and is a common unit for expressing the fee rate of a Bitcoin transaction.
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.