Unconfirmed Transaction
A transaction seen by the network but not yet included in a block, so its confirmation count is zero.
An unconfirmed transaction is pending in one or more node mempools. It has been broadcast, but miners or validators have not yet included it in a block accepted by the network.
Confirmation reliability depends on fees, mempool policy, conflicts, and network rules such as RBF. Users may be able to raise the fee, use CPFP, rebroadcast, or wait for congestion to clear.
Related terms
4 linkedExplore connected entries beyond the alphabetical index.
Mempool
→A temporary storage space in a node for pending transactions that have not yet been included in a confirmed block.
Replace By Fee (RBF)
→A Bitcoin node policy (BIP125) allowing an unconfirmed transaction to be replaced by a new one that pays a higher fee.
Zero Confirmation
→A transaction that has been broadcast but not yet included in a block, so it has zero confirmations.
Confirmations
→The count of blocks confirming a transaction, usually including the block that first contains it.
All terms and definitions may update as the Cryptionary improves.
