What is CPFP (child pays for parent)?
Unsticking a low-fee transaction by spending its output in a new, high-fee transaction, making the pair attractive together.
Miners evaluate packages, so a child transaction paying well above market can subsidise its parent. This works when you control an output of the stuck transaction — often the change output.
CPFP is the recipient-side answer to a stuck payment, where RBF is the sender-side one.
Related terms
RBF (replace-by-fee)
A signalling mechanism that lets an unconfirmed transaction be replaced by a version paying a higher fee.
Transactions & feesFee rate (sat/vB)
What a transaction pays per virtual byte of the space it occupies. Miners prioritise by fee rate, not by…
Transactions & feesMempool
The set of valid transactions a node has seen but that are not yet in a block — the queue competing for block…
This definition is part of the Bitcoin Logical glossary. For the fuller explanation, start with Lernen, or see the live numbers on Das Bitcoin-Signal.