US Patent 11689356 Approximate hash verification of unused blockchain output

An example operation may include one or more of receiving a location of an output stored on a data structure of a blockchain, where the location comprises a path of hashes generated by a reduced-step hash instead of a full-step hash of the blockchain, performing an approximate hash verification on the path of hashes based on the reduced-step hash values to verify whether the output is unused, and in response to a determination that the output is unused as a result of the approximate hash verification, approving a use of the output by a client associated with the output.