What Are Layer 2s?
Layer 2 solutions are scaling technologies built on top of Ethereum (Layer 1) that process transactions off the main chain while inheriting its security. They offer the same DeFi experience at a fraction of the cost—typically 90-99% cheaper than Ethereum mainnet.
Types of Layer 2s
Optimistic RollupsAssume transactions are valid by default, with a dispute period for challenges.
- Arbitrum, Optimism, Base
- Lower transaction costs
- EVM compatible (easy to port existing apps)
Use zero-knowledge proofs to verify transaction validity cryptographically.
- zkSync Era, Linea, Scroll, Starknet
- Faster finality (no dispute period)
- Higher security guarantees
Top Layer 2 Networks
Arbitrum- Largest L2 by TVL (~$10B+)
- Home to GMX, Pendle, Camelot
- Full EVM compatibility
- Mature ecosystem with most Ethereum protocols
- Second largest L2 ecosystem
- OP rewards for using protocols
- Superchain vision (unified L2 network)
- Velodrome as core DEX
- Backed by Coinbase
- Fastest growing L2 in 2024-2025
- Aerodrome as primary DEX
- Strong retail onboarding
- Leading ZK rollup
- Native account abstraction
- Growing DeFi ecosystem
Bridging to Layer 2s
Moving assets from Ethereum mainnet to L2s:
Native Bridges: Official bridges from each L2 (most secure, can be slow) Third-Party Bridges: Stargate, Across, Hop (faster, small fees) CEX Withdrawals: Many exchanges now support direct L2 withdrawalsDeFi on Layer 2s
Most major Ethereum protocols exist on L2s:
- Lending: Aave, Compound on Arbitrum/Optimism
- DEXs: Uniswap, Curve, native L2 DEXs
- Derivatives: GMX (Arbitrum), Synthetix (Optimism)
Why Use Layer 2s?
| Factor | Ethereum L1 | Layer 2 |
|---|---|---|
| Swap Cost | $5-50+ | $0.10-1 |
| Speed | 12 seconds | 2-4 seconds |
| Security | Native | Inherited |
| Protocols | All | Most major ones |