EIP-1559 Updates Across the Blocknative Mempool Data Platform

Blocknative Ethereum Web3

Ethereum's core gas fee marketplace mechanism is set to be upgraded at approximately 5:00am PST on August 5, 2021 – when EIP-1559 goes live as part of the London Hard Fork at block 12,965,000. This will update how Ethereum transaction fees are calculated, moving from a first-price auction to a hybrid system involving base fees and tips.

Given that this change impacts every Web3 builder and trader, we have updated our core Mempool API, Gas PlatformGas Estimator, and Mempool Explorer to each be EIP-1559-compliant and thereby help you and your users transact with confidence. Read on for full details. 

EIP-1559 Updates to Mempool API

There are three updates to our Mempool API to support EIP-1559:
  • Transaction type
  • Tip (maxPriorityFeePerGas)
  • maxFeePerGas

Transaction Types

We now support the transaction type in our Mempool API. Prior to the London Hard Fork, all transactions are type "0" and use the traditional gasPrice.  But after the London Hard Fork,  the new transaction type "2" will use maxPriorityFeePerGas and maxFeePerGas to specify the transaction fee.
Moving forward, both type 0 and type 2 transactions will be supported on Ethereum. Our API will continue to provide gasPrice for type 0 and will provide the new maxPriorityFeePerGas and maxFeePerGas fields for type 2 transactions. For Confirmed and Failed transactions we will also include the baseFeePerGas field.

Mempool API Changes

As soon as the London Hard Fork is live, our core Mempool API will begin delivering notifications that include the following new fields:
  • maxPriorityFeePerGas
  • maxFeePerGas
Mempool API will continue to include the gasPrice field where type= 0.

EIP-1559 Updates to Gas Platform

Once EIP-1559 is live on Ethereum Mainnet, the Gas Platform API will automatically add gas prediction fields for the new Type 2 fields to help your transaction successfully be included in the next block(s). The new fields are: 

  • baseFeePerGas: determined by the previous baseFeePerGas and block size
  • maxPriorityFeePerGas (tip): computed based on Blocknative's estimation model
  • maxFeePerGas: calculated from an initial heuristic, but will transition to model of block size estimation as we get data

Note that all existing Gas Platform API fields will continue to be supported. Hence, Gas Platform API payloads will expand to look like this: 


Every ecosystem participant can go hands-on with Gas Platform and receive API updates once every 5 seconds, while commercial Blocknative customers will receive API updates once every second.

EIP-1559 Updates to Gas Estimator

Once the London Hard Fork is live, we will update our Gas Estimator with an EIP-1559 toggle in the upper right. When enabled, Gas Estimator will show the following:
Screen Shot 2021-08-04 at 6.04.47 PM
If your wallet supports EIP-1559 (type 2) transactions, you will be able to use Gas Platform estimates to transact at your desired confidence interval. If your wallet does not support the new transaction type, you can turn off the EIP-1559 together to receive legacy gas estimates. 

EIP-1559 Updates to Mempool Explorer

Finally, we will be updating the Filter and Select controls available inside Mempool Explorer to add the EIP-1559-specific fields described above. This will enable all Mempool Explorer users to update their existing Subscriptions to be aware of – and responsive to – data fields related to EIP-1559. 


Preparing for the London Hard Fork and EIP-1559

The Ethereum Foundation has indicated that gas prices may fluctuate – perhaps substantially – for a short period immediately after EIP-1559 goes live. Our data science team will be monitoring the Ethereum network as it reaches a new equilibrium so that we can refine our gas price models and provide the Web3 ecosystem with the most accurate and actionable gas estimations. 

Please stay tuned for updates as we expand and refine our support for EIP-1559 across our portfolio. As always, please join our Discord Community if you have questions, concerns, or recommendations.

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