Starknet vs Arbitrum One

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

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

Starknet C

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

Centralized sequencer & prover
Smaller ecosystem than OP/Arbitrum

Arbitrum One C+

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

Centralized sequencer
Security Council can fast-track upgrades

Bottom line

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