State_trie

Chapter 28: State & Merkle Trie Structures

Overview

Ethereum uses Merkle Tries to efficiently store and verify state data.

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28.1 Merkle Patricia Trie

Ethereum uses a Modified Merkle Patricia Trie (MPT) for state storage.

Trie Structure

                    Root Hash
                        │
        ┌───────────────┼───────────────┐
        │               │               │
    Prefix          Path          Suffix
        │               │               │
     (nibbles)     (key)         (value)

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28.2 Trie Types

Trie	Purpose
State Trie	Account balances, code, storage
Transaction Trie	Block transactions
Receipt Trie	Transaction execution results

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28.3 State Access

// Get account balance via state trie
eth.getBalance("0x...", "latest")

// Get contract storage
eth.getStorageAt("0x...", 0, "latest")

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Summary

• Merkle Tries enable efficient state verification
• State trie contains all account data
• Patricia Trie optimizes path encoding

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Last Updated: 2026-02-20