Arbitrum One vs Starknet

Which is more decentralized — Arbitrum One or Starknet? A side-by-side on consensus, nodes, clients and governance.

	Arbitrum One	Starknet
Grade	C+	C
Type	L2 · Optimistic rollup	L2 · ZK rollup
Nakamoto / stage	Stage 1	Stage 1
Node / validator set	Inherits Ethereum security	Inherits Ethereum security
Clients / sequencer	Single sequencer (Offchain Labs)	Single sequencer (StarkWare)
Governance	Arbitrum DAO + Security Council	Starknet governance (token + council)
Key risk	Centralized sequencer	Centralized sequencer

Arbitrum One C+

L2BEAT Stage 1
Permissionless exits + 7-day upgrade timelock
Active Arbitrum DAO

Centralized sequencer
Security Council can fast-track upgrades

Starknet C

Validity proofs (no challenge window)
L2BEAT Stage 1
Native account abstraction

Centralized sequencer & prover
Smaller ecosystem than OP/Arbitrum

Bottom line

Among the most decentralized L2s — sequencer decentralization is the remaining step. Strong cryptographic guarantees; operational decentralization is in progress.