🔨 Building Your First Merkle Tree
Learn how to construct a Merkle tree from leaf nodes to root hash
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0 / 5 completed🔨 Building a Merkle Tree
Let's build a Merkle tree step by step! Watch how data at the leaves gets hashed and combined up to a single root hash.
📋 Construction Algorithm
Take each transaction and compute its hash. These become the leaf nodes.
Leaf₂ = Hash("TX2")
Leaf₃ = Hash("TX3")
Leaf₄ = Hash("TX4")
Concatenate adjacent hashes and hash them together to create parent nodes.
Parent₂ = Hash(Leaf₃ + Leaf₄)
Continue combining pairs level by level until only one hash remains - the Merkle root!
🎮 Interactive Tree Builder
Add or remove transactions, then watch the tree build automatically:
🧮 Complexity Analysis
Linear time to build, but logarithmic height makes verification efficient!
Only 10 hashes needed to verify any single transaction!
⚠️ Edge Cases
If you have an odd number of nodes at any level, duplicate the last node.
Then pair: Hash(TX1+TX2), Hash(TX3+TX3)
With just one transaction, the hash of that transaction IS the Merkle root.
Bitcoin blocks always have at least a coinbase transaction, so never truly empty.
💡 Key Insights
Always build from leaves up to root. Can't start from root and work down!
Same transactions always produce same Merkle root. Order matters!
Each level can be computed in parallel - great for performance!