Layer 2 Complete gids
Everything you need to know about Ethereum Layer 2s: Arbitrum, Optimism, Base, zkSync, Starknet, and more. Compare fees, speed, and security.
What is Layer 2?
Layer 2 (L2) refers to scaling solutions built on top of Ethereum (Layer 1) that process transactions off-chain while inheriting Ethereum's security. Think of it like an express lane on a highway - the same destination, but much faster and cheaper.
L2s bundle (or "roll up") hundreds of transactions into a single proof that gets posted to Ethereum. This means you get:
- 10-100x lower fees - Pay cents instead of dollars
- Higher throughput - 1000s of TPS vs Ethereum's ~15 TPS
- Same security - Transactions are ultimately secured by Ethereum
- EVM compatibility - Same tools, portemonnees, and dApps work
Why Layer 2s Exist
Ethereum can only process ~15 transactions per second, leading to high fees during congestion. The "scalability trilemma" explains why simply increasing throughput would compromise security or decentralization.
The Scalability Trilemma
Blockchains must balance three properties. Layer 2s inherit Ethereum's security and decentralization while adding scalability.
Types of Rollups
There are two main approaches to Layer 2 scaling, each with different tradeoffs for speed, cost, and security.
Optimistic vs ZK Rollups
How it works
Transactions are assumed valid by default. A 7-day challenge period allows anyone to submit a "fraud proof" if they detect invalid transactions. If no challenge is raised, the transactions are finalized on Ethereum.
Voordelen
- + Full EVM compatibility
- + Lower computational cost
- + Mature technology
- + Large ecosystems
Nadelen
- - 7-day opname delay
- - Relies on honest verifiers
- - Higher data costs
L2 Ecosystem Comparison
Total Value Locked (TVL) indicates how much capital is deployed on each L2. Higher TVL generally means more liquiditeit, more dApps, and a more mature ecosystem.
Total Value Locked (TVL) by L2
Data as of January 2026. Source: L2Beat
Layer 2 Networks
Click each network to see detailed information about TVL, fees, finality time, and ecosystem size.
Fee Comparison
See how much you can save on transaction fees by using Layer 2s. Adjust the Ethereum gas price and transaction type to compare costs.
Fee Comparison Calculator
How to Bridge to L2
To use a Layer 2, you need to "bridge" your ETH or tokens from Ethereum mainnet. Compare official bridges vs third-party solutions.
Bridge to Layer 2
Recommended for security. Uses the native rollup bridge for maximum safety.
Security tip: Official bridges are slower but most secure. Third-party bridges are faster but add smart contract risk. For large amounts, prefer official bridges.
Which L2 Should You Use?
For DeFi Trading
Arbitrum One - Largest TVL, most liquiditeit, supports GMX, Aave, Uniswap
Best for: Swaps, lending, perpetual trading
For NFTs & Social
Base - Growing NFT ecosystem, social apps, Coinbase integration
Best for: Minting, social dApps, mainstream users
For Airdrops
zkSync Era, Linea, Scroll - Newer networks with potential token launches
Best for: Early adopters seeking airdrop eligibility
For Lowest Fees
Polygon zkEVM, Scroll - Extremely low transaction costs
Best for: High-frequency transactions, gaming
For Innovation
Starknet - Native account abstraction, Cairo language, highest theoretical TPS
Best for: Developers, cutting-edge DeFi
The Future of Layer 2s
EIP-4844 (Proto-Danksharding)
Implemented in 2024, this reduced L2 fees by 10-100x by introducing "blob" data that expires after ~18 days.
Full Danksharding
Coming ~2026, will increase data availability by 100x, enabling even cheaper L2 transactions.
L3s and App Chains
Application-specific chains building on top of L2s for even more customization and performance.
Cross-L2 Communication
Projects like Superchain (Optimism) and AggLayer (Polygon) aim to enable seamless asset movement between L2s.