Storage slot calculator

Follows the Solidity storage layout rules, ERC-7201 and EIP-1967.

Mapping slot

Base slot (declaration position)

Key type

Key

Nested keys (optional; one "type,value" per line, applied after the first key)

Dynamic array element

Array slot

Index

Slots per element

ERC-7201 namespace

Namespace id

EIP-1967 proxy slots

Read a live slot

Chain

Contract

Slot

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