Base is an Ethereum layer 2 network incubated by Coinbase. It runs transactions on its own chain, publishes the data to Ethereum as blobs, and settles withdrawals through proofs checked on Ethereum. As of November 2026, L2BEAT rates it a Stage 1 optimistic rollup. A single sequencer orders transactions and Coinbase earns its fees, but contract upgrades also need an independent Security Council, and users can force transactions through Ethereum.
What Base is, and what it is not
Base is a layer 2: a separate chain that processes transactions cheaply and uses Ethereum for its final record. It opened to the public on August 9, 2023, and fees are paid in ETH.
Keep the chain and the company apart in your head. An exchange account at Coinbase is custodial: Coinbase holds the assets for you. Base is a public network that you can reach from a self-custody wallet, with no Coinbase account involved.
It is also a business line. Coinbase's 2025 annual report says the company "generates revenue from sequencer fees paid each time a transaction is processed on the Base blockchain."
Is Base still built on the OP Stack?
Base launched on the OP Stack, the open-source rollup software created by Optimism. Many guides still describe it that way, but the picture has changed.
In February 2026, Base announced it would consolidate on its own base/base codebase, ship one official Base client, and move to six smaller hard forks a year, double its previous pace. It also gave Optimism's Security Council seat to another independent signer. L2BEAT records Base decoupling from Optimism's Superchain governance on March 4, 2026.
The break is partial. Base said it will stay compatible with the OP Stack specification, its protocol documents still use contract names such as OptimismPortal, and L2BEAT still lists it as built on the OP Stack. The fair summary is OP Stack heritage with an independent roadmap.
How a Base transaction reaches Ethereum
A Base transaction gains stronger confirmation in stages, according to Base's timing documentation.
- Flashblock, about 200 milliseconds. The sequencer, the node that orders transactions, gives an early confirmation. This is a preview. L2BEAT notes these confirmations are not enforced by the protocol and can be absent or reorganized.
- L2 block, about 2 seconds. The sequencer packs transactions into a Base block.
- Batch on Ethereum, about 2 minutes. A component called the batcher compresses the data and posts it to Ethereum.
- Ethereum finality, about 20 minutes. The batch is now old enough on Ethereum to be effectively irreversible.
- State claim on Ethereum. A proposer later posts a claim about Base's state. Withdrawals rely on that claim.
Swaps and transfers inside Base do not wait for step 5. Only withdrawals to Ethereum through the official bridge do.
What you pay: an execution fee plus an Ethereum data fee
Each Base transaction pays two main costs: an L2 execution fee and an L1 security fee for publishing data on Ethereum. Base's documentation says the L1 fee is typically the larger of the two. This is the same gas fee idea as on Ethereum, with a data cost added.
Here is the execution part, using Base's own example:
- Minimum base fee: 0.005 gwei.
- A 200,000-gas transaction: 200,000 × 0.005 gwei = 1,000 gwei, or 0.000001 ETH.
- With ETH at $2,000, that is about $0.002.
That figure leaves out any priority fee and the L1 fee, so your real cost will be higher. The base fee also rises during congestion, by up to 4% per block.
The L1 fee follows Ethereum's costs. Since March 2024, Base has posted its data as blobs, temporary data attachments on Ethereum with their own fee market. Nodes only have to keep blobs for about 18 days, which is a large part of why they are cheap. When data load runs high, Base can also delay transactions through what it calls DA throttling, whatever priority fee you offer. For more on this area, see our scaling coverage.
From fault proofs to multiproofs: why withdrawals take days
A classic optimistic rollup assumes state claims are valid unless someone proves fraud during a challenge window. Base added permissionless fault proofs in October 2024, with withdrawals taking about 7 days.
In May 2026, the Azul upgrade replaced that design with a multiproof system. A proposal now needs a positive proof before it can finalize, from one of two sources:
- A TEE proof. A trusted execution environment, in this case an AWS Nitro Enclave, re-executes the blocks and signs the result. It is cheap and fast, but Base itself notes that trust rests with the hardware authority.
- A zero-knowledge proof. This relies on mathematics instead of trusted hardware, but it costs more to generate. The ZK path is permissionless and can override an invalid TEE-backed claim.
So Base no longer fits the classic picture of "assume valid, wait for fraud," even though L2BEAT still classifies it as an optimistic rollup. The remaining delay exists for a narrower reason. Base says it leaves time to detect and disable a faulty prover.
| Route | Typical wait | The catch |
|---|---|---|
| Official bridge, single proof | About 5 days (cut from 7 in June 2026) | The common path, with two Ethereum transactions to pay for |
| Official bridge, TEE and ZK proofs | 1 day | Rarely used, because ZK proofs are costly to generate |
| Third-party bridge | Sooner, using the bridge's own liquidity | You take on that bridge's own risks |
| Activity inside Base | No withdrawal wait | Your funds stay on Base |
A withdrawal of 1 ETH through the official bridge runs like this. You start it on Base. You wait about 20 to 60 minutes for Base's state to be proposed on Ethereum. You send a "prove" transaction on Ethereum. You wait about 5 days, then send a "finalize" transaction, and the ETH arrives. You pay Ethereum gas on both of those steps.
The sequencer is Base's biggest centralization point
Base's own documentation says it "currently operates with a single active sequencer." L2BEAT reports five coordinated instances for availability, but only the leader produces blocks, and they do not create independent operators.
That has three practical effects:
- Outages stop the chain. A failed sequencer handoff halted blocks for 33 minutes on August 5, 2025. In late June 2026, a sequencer bug and its aftermath caused outages of 116 and 20 minutes.
- One party orders transactions. Ordering affects who can capture MEV. L2BEAT notes that ordering each Flashblock by priority fee is a policy, not something the protocol's rules enforce.
- Censorship is possible for a time. The sequencer can refuse to include your transaction in real time.
The sequencer cannot simply invent balances, because anyone can rebuild the chain from the data on Ethereum. There is also an escape route. You can send a transaction directly to the Ethereum contract, and it must be included within about 12 hours. L2BEAT puts a fully forced exit at about 5 days and 12 hours, with a permissionless ZK proof and a 0.05 ETH bond. That route exists mainly for emergencies, and most users would need help to use it.
What Coinbase controls, and what it doesn't
Coinbase has significant operational power and does not hold sole control of the contracts. The table summarizes L2BEAT's permissions data and Base's Security Council page as of November 2026.
| Power | Who holds it | Limit |
|---|---|---|
| Upgrade core contracts | Coinbase's 3-of-6 multisig and the 8-of-11 Security Council, together | Neither can do it alone, but there is no upgrade delay |
| Approve TEE signers | Coinbase's multisig | No Security Council sign-off needed; a ZK proof can still override a bad TEE claim |
| Replace the sequencer, set gas configuration | Base Multisig 1, a 3-of-12 multisig | Forced inclusion through Ethereum remains |
| Pause withdrawals | Base Multisig 1 as incident responder; the governance multisig also has pause power | Base Multisig 1's pauses expire after about 3 months, and it cannot extend them |
| Move funds in your self-custody wallet | Nobody but you, through your keys | Tokens' own issuers may still have freeze powers |
The upgrade row is the one to read twice. Coinbase and at least 8 Council members can together change the contracts holding bridged funds, and L2BEAT shows no waiting period for users to leave first. The Council has 11 members, 6 entities and 5 individuals, but the people behind the entities are not published. You are trusting that group, even though no single party in it can act alone.
What Stage 1 means for Base
L2BEAT's stages rate how far a rollup has moved from operator control to enforced rules. Base reached Stage 1 on April 29, 2025. L2BEAT says it meets all Stage 1 requirements and passes its "walkaway test."
Stage 2 is the top rating, and L2BEAT lists two blockers:
- "Upgrades unrelated to onchain provable bugs provide less than 30d to exit."
- "The Security Council's actions are not confined to onchain provable bugs."
Base calls Stage 2 its next milestone. In November 2026, L2BEAT showed about $14.7 billion in value secured on Base, so these trust assumptions carry real weight.
Does Base have a token?
No. As of November 2026, Base has no network token, and fees are paid in ETH. The history is short:
- At launch in 2023, Coinbase said, "We currently do not plan to issue a new network token."
- In September 2025, creator Jesse Pollak said Base would be "exploring a network token" and called it early.
- Reporting on the Cobalt upgrade, live on September 30, 2026, said it involved no token launch.
B20, which arrived with the Beryl upgrade, is a standard for issuing tokens on Base, not a Base token. Treat any claim of an official token or airdrop as a likely airdrop scam until Base itself confirms it on its own channels.
Key takeaways
- Base is a Coinbase-incubated Ethereum layer 2 that pays fees in ETH and posts its data to Ethereum as blobs.
- It began on the OP Stack and left Optimism's governance in 2026, while keeping compatibility with the OP Stack specification.
- Since 2026, withdrawals need a positive TEE or ZK proof, and the usual wait is about 5 days.
- One sequencer orders transactions, which creates outage and censorship risk, though forced inclusion through Ethereum is available within about 12 hours.
- Upgrades need both Coinbase's multisig and the Security Council, but they carry no delay, which is one reason L2BEAT rates Base Stage 1 and not Stage 2.
- Base has no network token as of November 2026.
Sources
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