# Comparing Ethereum layer 2s: the questions behind a cheap transfer Compare a layer-2 network by what Ethereum verifies, where users can obtain its data, who orders transactions, who can change its contracts and how assets exit. Also check application compatibility and the exact token route. A low fee or a familiar EVM interface answers only part of that comparison; a broad label such as rollup does not describe every current deployment detail. Evidence: [Ethereum layer 2](https://ethereum.org/en/layer-2/); [Inside Arbitrum Nitro](https://docs.arbitrum.io/how-arbitrum-works/inside-arbitrum-nitro); [OP Stack overview](https://docs.optimism.io/stack/getting-started); [ZKsync protocol introduction](https://docs.zksync.io/zksync-protocol/rollup) Canonical: https://degreesofsatoshi.com/encyclopedia/comparing-ethereum-layer-2s/ Published: 2026-10-02 Substantively modified: 2026-10-02 Independently verified by an automated reviewer: 2026-10-02T19:27:58.939Z Data current through: 2026-10-02 AI-assisted research and drafting with a separate automated source-verification pass; no external expert or named human review is implied. ## Key facts - **Data:** Ethereum publication and committee-backed availability have different assumptions. ([Inside Arbitrum Nitro](https://docs.arbitrum.io/how-arbitrum-works/inside-arbitrum-nitro)) - **Proofs:** Optimistic and validity systems establish state claims through different mechanisms. ([Inside Arbitrum Nitro](https://docs.arbitrum.io/how-arbitrum-works/inside-arbitrum-nitro); [ZKsync protocol introduction](https://docs.zksync.io/zksync-protocol/rollup)) - **Compatibility:** EVM tooling compatibility can still have documented execution differences. ([ZKsync EVM interpreter](https://docs.zksync.io/zksync-protocol/era-vm/evm-interpreter/overview); [OP Stack overview](https://docs.optimism.io/stack/getting-started)) ## Ask what evidence the parent chain checks For a rollup, identify how state claims are verified and how data is made available. A validity proof and an optimistic challenge mechanism are different designs. A committee certificate adds an availability assumption distinct from publishing full data to Ethereum. Then examine the actual implementation and operational controls. A theoretical design description does not tell you whether every feature is deployed or who can upgrade the bridge contracts. Evidence: [Ethereum layer 2](https://ethereum.org/en/layer-2/); [Inside Arbitrum Nitro](https://docs.arbitrum.io/how-arbitrum-works/inside-arbitrum-nitro); [ZKsync protocol introduction](https://docs.zksync.io/zksync-protocol/rollup) ## Two cheap transfers can hide different exit paths Suppose two networks both quote a small local transfer fee. One withdrawal route may require several later Ethereum transactions and waiting conditions, while another uses a different proof and finalization path. The local transfer price alone cannot compare the complete cost or time of moving funds back. Use the whole intended journey: entry, activity and exit. Quote live costs only with their network, action and observation time. Evidence: [OP Stack withdrawal flow](https://docs.optimism.io/stack/transactions/withdrawal-flow); [Base transaction finality](https://docs.base.org/specifications/transactions/transaction-finality) ## Match the network to the operation A familiar EVM application, a native smart-account application and a cross-chain treasury can have different requirements. Check wallet support, execution differences, destination asset identity and recovery options for that particular task. Keep the result as a documented comparison rather than a universal safety ranking. A configuration or upgrade can change a material assumption after a comparison is written. Evidence: [ZKsync EVM interpreter](https://docs.zksync.io/zksync-protocol/era-vm/evm-interpreter/overview); [Starknet accounts](https://docs.starknet.io/learn/protocol/accounts.md); [Ethereum layer 2](https://ethereum.org/en/layer-2/) ## Questions ### Is the lowest displayed fee enough to choose a network? No. Include the intended transfer route, later fees, waiting conditions, asset support and the network’s documented trust assumptions. Evidence: [Ethereum layer 2](https://ethereum.org/en/layer-2/); [OP Stack withdrawal flow](https://docs.optimism.io/stack/transactions/withdrawal-flow) ### Does using Ethereum settlement make every L2 equally secure? No. Data availability, proof deployment, administrative controls and bridges can differ. Inspect the particular network rather than relying only on its category. Evidence: [Ethereum layer 2](https://ethereum.org/en/layer-2/); [Inside Arbitrum Nitro](https://docs.arbitrum.io/how-arbitrum-works/inside-arbitrum-nitro); [ZKsync protocol introduction](https://docs.zksync.io/zksync-protocol/rollup) ## Claims and scope ### comparing-ethereum-layer-2s-quick-answer Compare a layer-2 network by what Ethereum verifies, where users can obtain its data, who orders transactions, who can change its contracts and how assets exit. Also check application compatibility and the exact token route. A low fee or a familiar EVM interface answers only part of that comparison; a broad label such as rollup does not describe every current deployment detail. Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null} ### comparing-ethereum-layer-2s-fact-data Data: Ethereum publication and committee-backed availability have different assumptions. Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null} ### comparing-ethereum-layer-2s-fact-proofs Proofs: Optimistic and validity systems establish state claims through different mechanisms. Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null} ### comparing-ethereum-layer-2s-fact-compatibility Compatibility: EVM tooling compatibility can still have documented execution differences. Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null} ## Sources - [Ethereum layer 2](https://ethereum.org/en/layer-2/) — ethereum.org contributors. Rollup comparison dimensions and limits of transferring broad labels to a named deployment. Locator: Rollups; sidechains; bridges; considerations. Retrieved: 2026-10-02T18:55:27.801Z. - [Inside Arbitrum Nitro](https://docs.arbitrum.io/how-arbitrum-works/inside-arbitrum-nitro) — Offchain Labs. Nitro rollup execution and Ethereum batch publication versus AnyTrust committee assumptions. Locator: Transaction journey; rollup; AnyTrust. Retrieved: 2026-10-02T18:55:27.094Z. - [OP Stack overview](https://docs.optimism.io/stack/getting-started) — Optimism. Reusable rollup software and chain-specific configuration. Locator: OP Stack; components; deployments. Retrieved: 2026-10-02T18:55:27.607Z. - [ZKsync protocol introduction](https://docs.zksync.io/zksync-protocol/rollup) — ZKsync. Validity-proof execution and Ethereum settlement; deployment-specific compatibility. Locator: ZKsync Era; execution; proofs. Retrieved: 2026-10-02T18:55:27.606Z. - [ZKsync EVM interpreter](https://docs.zksync.io/zksync-protocol/era-vm/evm-interpreter/overview) — ZKsync. EVM bytecode interpretation and EraVM execution have documented compatibility boundaries. Locator: Execution environments; interpreter. Retrieved: 2026-10-02T18:55:28.128Z. - [OP Stack withdrawal flow](https://docs.optimism.io/stack/transactions/withdrawal-flow) — Optimism. L2-to-L1 withdrawals require distinct onchain stages and protocol waits. Locator: Initiate; prove; finalize; fault proofs. Retrieved: 2026-10-02T18:55:27.608Z. - [Base transaction finality](https://docs.base.org/specifications/transactions/transaction-finality) — Base. Distinguish Base preconfirmation, block inclusion, Ethereum data finality and withdrawal completion. Locator: Finality stages. Retrieved: 2026-10-02T18:55:27.802Z. - [Starknet accounts](https://docs.starknet.io/learn/protocol/accounts.md) — Starknet. Native contract-account validation and execution differ from Ethereum EOAs. Locator: Account abstraction; validation. Retrieved: 2026-10-02T18:55:28.472Z. ## Revision history - 2026-10-02: First publication after primary-source research and separate automated verification. ## Cite this entry Degrees of Satoshi editorial project. “Comparing Ethereum layer 2s: the questions behind a cheap transfer.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/comparing-ethereum-layer-2s/