Definition
What is Opcode?
An opcode is a single low-level instruction the EVM understands, such as ADD, SLOAD (read storage), SSTORE (write storage), or CALL, each with a defined gas cost.
Gas optimisation is ultimately about choosing patterns that compile to cheaper opcodes: fewer SSTOREs, fewer external CALLs, tighter storage packing. Reading the opcode-level gas schedule is how tools such as Chain Fit reprice one execution across chains with different schedules.
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Definition by Adwait Keshari, founder of Monsmith.
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