May 2023 – opBNB New Layer 2

  1. Introduction
  2. Optimistic Rollups
  3. What is opBNB
  4. Why opBNB
  5. What lies ahead
  6. Conclusion


The blockchain trilemma (security, decentralisation and scalability) is still the most important question yet to be answered. Companies and communities are coming up with different types of solutions to the problem. In recent days there have been some interesting developments.

Binance launched the opBNB Testnet on 19 June 2023. opBNB is Binance’s solution to the scalability problem. opBNB is an EVM compatible layer 2 chain which uses Optimism OP stack to enhance BSC scalability while preserving security and affordability. opBNB uses optimistic rollups to reach the speeds of 4000 transactions per second (tps) at a cost of around US$ 0.005. This is significantly higher than EThereum’s 30 tps.

Optimistic rollups

Rollups are gaining huge popularity in recent years. It is supposed to be the solution to the scalability problem and is right on the money. Rollups are a layer 2 solution built on top of layer 1. Data availability,transaction execution and consensus, all happening in the same layer without compromising security is very difficult.  This is where rollups come in to play their part. Rollups uses a new layer to execute the transaction while using the security of the layer 1 blockchain. This helps to scale a huge number of transactions without compromising security and decentralisation.

In Optimistic rollups, it is assumed that the transactions are valid until proven invalid. This is why they are called “optimistic”. They rely on validators to check each transaction and dispute them if invalid. Due to this there exists a withdrawal period where users must wait for sometime before being able to withdraw the money. Validators use fraud proof mechanisms to dispute invalid transactions. Since optimistic rollups are not using cryptographics proofs for every transaction block, they cost very less. 

What is opBNB

opBNB is a layer 2 scaling solution built on top of binance layer 1 chain. It is using the Optimism OP stack to address the scalability issue faced by BNB smart chain. It includes the usage of Optimistic rollups to process transactions off-chain, before batching multiple transactions into one and submitting it to the mainnet. This drastically reduces the burden on mainnet. 

Sequencers are the ones who aggregate the transactions and submit the rollup contract back to the main chain. This helps the BNB chain to help have high throughput and low fees.

Why opBNB

Enhanced Scalability

opBNB can achieve a capacity of 100 million gas per second, while helping it to support over 4000 transactions per second (Ethereum can do 30 tps). This will give a massive boost to the number of daily users on the chain. The Web3 gaming industry will be super attracted to it since this will reduce latency and make the system more responsive. Time lag while collecting in-game assets will be drastically reduced. This will provide a better user experience.

Cost Efficiency

The biggest advantage of all is the cost. opBNB can execute a transaction costing less than US$ 0.005. This is less than the average processing fees for major credit cards.

The cost on Ethereum is a few to a couple hundred dollars. opBNB provides significantly reduced gas fees, making it affordable for a wide user base.


Scalability had been achieved but not at the cost of decentralisation and security. opBNB uses a fraud-proving mechanism to secure all off-chain transactions.The sequencers, provers, and verifiers ensure secure transactions which are transparent and verifiable to help build a healthy and safe app environment.


opBNB is EVM compatible. This means that the developers will be able to develop easily using the familiar Ethereum tools and dApps. This will help developers to attract more users. The fact that opBNB can offer high throughput and lower transaction fee will automatically attract users for seamless experience. opBNB is also cross chain compatible, which means that users can transfer tokens between opBNB and other layer 2 solutions.

Future Proof

The roadmap for opBNB is already in place. The testnet is already live and is receiving active feedback from the developers. The mainnet is considered to go live in September 2023. With a flexible and attractive framework, developers can easily adapt and experiment their new ideas. The BNB ecosystem already has a significantly large user base, many of whom trust the brand. This will surely provide them with a competitive advantage.

What lies ahead

The BNB chain now has implemented both zkBNB and opBNB. This makes the chain compete directly with Ethereum’s layer 2 solutions like Arbitrum and Optimism. The BNB chain is still very small when compared to the Ethereum ecosystem. In terms of Total value locked in the chain, BSC is behind Ethereum and Tron. But the BNB chain is promoting a lot of innovative development in its ecosystem, providing better incentive for the developer.


opBNB is definitely the preferred new layer 2 solution. With over 4000 tps and less than $0.005 per transaction, it is the most attractive on the market. opBNB can integrate well within the BNB ecosystem and leverage the ecosystem benefits like the decentralised data storage system BNB Greenfield. The BNB ecosystem is expanding fast with new and innovative solutions. opBNB has the potential to lead the growth and adaptability of the blockchain industry.