What Is the Primary Difference between Optimistic Rollups and ZK-Rollups?

Optimistic Rollups assume transactions are valid by default and use a fraud-proof system where a challenge period allows anyone to dispute an invalid transaction. ZK-Rollups, conversely, use zero-knowledge proofs (specifically SNARKs or STARKs) to cryptographically prove the validity of every off-chain transaction batch before it is submitted to the Layer 1 chain.

This fundamental difference results in ZK-Rollups having near-instant finality on Layer 1, while Optimistic Rollups have a delay due to the challenge window.

How Does a Layer-2 Solution Ensure the Security of Its Off-Chain Data?
What Layer 2 Solution Eliminates the Need for a Long Withdrawal Period?
What Is the Fundamental Difference between Optimistic Rollups and ZK-Rollups?
How Do Fraud Proofs in Optimistic Rollups Work to Secure Funds?
Differentiate between Optimistic Rollups and ZK-Rollups
How Does the “Fraud Proof” Mechanism Work in an Optimistic Rollup?
What Specific Zero-Knowledge Proof Technology Is Commonly Used in ZK-Rollups for Financial Transactions?
How Does the Withdrawal Period of Optimistic Rollups Affect Decentralized Finance (DeFi) Liquidity?

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