AssumeUTXO

AssumeUTXO is a proposed, optional setting that would allow users to make use of their Bitcoin node before initial block download (IBD) is complete. IBD is one of the most prohibitive costs to running a node, so reducing or hiding this burden is an important improvement for Bitcoin’s usability and decentralization.

AssumeUTXO allows users who are launching full nodes to first download a full copy of the UTXO set from a node, allowing their node to immediately start crafting, querying, and broadcasting transactions. In the background, the full node still downloads and verifies each block, maintaining the trustless nature of Bitcoin.

Without AssumeUTXO, users must wait to craft and query transactions until their node has downloaded and validated the entire blockchain, a process that can take up to two weeks depending on the computer.