Definition
A block template is a provisional data structure constructed by a miner or validator that specifies which pending transactions and metadata will form the next candidate block. It includes an ordered set of transactions selected from the mempool, protocol-required fields such as parent block reference and timestamps, and configuration choices that influence block contents prior to final block assembly and submission.
In Simple Terms
A block template is a draft version of the next block that a miner or validator prepares before it becomes part of the blockchain. It lists which waiting transactions will be included and sets basic block information, acting as the blueprint that is turned into an actual block if it is successfully produced.
Context and Usage
The term block template appears in discussions about block production, mining software, validator clients, and transaction selection policies. It is relevant when analyzing how transactions move from the mempool into a block, how gas fees and MEV considerations influence inclusion, and how different node or client implementations structure candidate blocks before they are finalized and propagated across the network.