Mempool Explorer

Mempool Explorer™ lets you go hands-on with real-time Ethereum data. Watch addresses, filter and select events, and determine what data you want to build with.


This documentation describes how to use Blocknative’s Mempool Explorer. Mempool Explorer enables you to create data feeds for the addresses (wallet or contract) that you care about. Add filters and push your feed into a webhook that you can start building with.

Mempool Explorer uses our API, which has rate limits. Please see Rate Limits for more details.

Getting Started

Create Your Feed

  1. Go to to begin creating your feed.

  2. Create a subscription by filling the new subscription card. Enter a name and Ethereum address.

Create New Subscription Card

3. Click Create and Mempool Explorer will subscribe to all transactions that involve that address. You will see events appear on the panel on the right as new transactions occur:

Sample Event

Creating Subscriptions

Subscriptions enable you to monitor any smart contract or wallet address. All subscriptions need a name and an address.

When you land on Mempool Explorer, an empty Create New Subscription card will be waiting for you to fill. You can create additional subscriptions by clicking the New Subscription Button:

Create new subscription button


See how to get started with Mempool Explorer in this screencast:

Introductory Walk Through of Mempool Explorer

Add local ABI to interpret and filter transaction data in this screencast:

Custom ABIs with Mempool Explorer

Compose subscriptions for external services with webhooks in this screencast:

Compose with Webhooks in Mempool Explorer


Once a subscription has been created, Mempool Explorer will display an event for every transaction that involves that address. You may want to limit displayed events to transactions that fit a particular criteria and to do this you can create filters to apply to each event.

Click the "+" icon next to the Global Filter toggle to start creating a Global Filter. Global Filters filter all of your subscriptions.

Global Filter Toggle

You will see the filter form appear at the top of the page:

Filter Form

You can then traverse the event object schema to select the properties that you would like to create a comparison that any new events must pass before being displayed:

Traversing the event object schema

The type of comparison that is used to create a filter depends on the parameter that is selected. The following is a complete list of the comparisons that can be made:


Used to check that a property value is not undefined (that is to say is defined).


Used to match string values and tests for an exact match.


Used to match string values that are not the value that has been inputted.


Used to select a list of possible string values, where if there is a match on any one of them then the comparison has passed.

greater than

Used to compare numerical values against an inputted value

greater than or equal to

Used to compare numerical values against an inputted value

less than

Used to compare numerical values against an inputted value

less than or equal to

Used to compare numerical values against an inputted value

Once you are happy with your filter comparison, click the "Add" button to add it to the list of filters that are being applied.


Blocknative transaction events are very detailed and contain a lot of data, all of which you might need. If you would like to reduce the amount of data delivered in events to only key information, then you can Select the information you need to do just that!

Click the "+" icon to start filling a Select Form and you will see it appear at the top of the page. Global Select affects all of your subscriptions.

Global Select Form

You can then traverse the notification object schema to select the properties that you would like to be included in the event:

Traversing the event object to find the properties you want

Once you have settled on a property that you want to include in the event, click the "add" button which will add it to your Select list include.

By default every property is selected with the event. As soon as you Select any property, the event will start displaying only the properties selected.

Global vs Local

You can Filter and Select globally for all of your subscriptions or locally for each subscription. This allows for ease of use and flexibility in how you modify displayed events.

A Global Filter or Select applies to all of your subscriptions and is located at the top of your subscriptions tab:

Global Controls

A local Filter or Select applies only to the subscription they are added to and are located on the subscription card:

Subscription card with Filter and Select controls

Contract ABI

If the address you are creating a subscription for is a contract address, then you can upload the ABI for that contract and Mempool Explorer will automatically decode the input data for any contract calls for that address.

You can upload a .json file of the ABI by clicking the ABI button on the subscription card:

The ABI button located on the subscription card (Neutral State)

The ABI button has four (4) total states:

  • Neutral, indicating no ABI is detected.

  • Green, indicating a working ABI has been detected or uploaded and contract events are being decoded successfully.

  • Yellow, indicating the ABI uploaded is incorrect for that contract address. This status is shown after 10 or more events have failed to decode successfully.

  • Red, indicating the uploaded ABI is an invalid object.

Sample ABI State (Red)

If the uploaded ABI for the contract is invalid, Mempool Explorer will change the ABI indicator to Yellow and send a notification indicating the ABI provided has failed to decode the input after 10 events related to that contract address:

Sample Invalid ABI Notification

Blocknative backend infrastructure automatically decodes contract input data for common ERC20 and ERC721 tokens and other popular contracts, so there is no need to upload an ABI for these contract types. For a full list head to the API Docs.

Saving / Loading Configurations

To be able to save and load your configuration, you will need to log in to your Blocknative account.

Setup Configuration

  1. Create a Blocknative account by clicking the Login button on Mempool Explorer and following the instructions. Account creation requires email confirmation to complete.

  2. Blocknative will create a Default API key for your account that you can save your configuration to. You can create additional API keys from your account dashboard on

Once you have an account, you can login to Mempool Explorer by clicking the Login button at the top right. After logging in, the configurations menu button will display where the Login button was:

Configurations button

Clicking the Configurations Button will display the configurations menu, allowing for API key selection, the ability to load an existing feed if one is currently saved to that key and to save a new configuration to the selected key.

Configurations Menu

The "Load" button will be disabled if there isn't a configuration currently saved to the selected API key

Once a configuration is saved to your key, it will be applied to any webhooks that you have saved to that key/blockchain/network combination and will produce the same feed that you see within Mempool Explorer.

Export Current Configuration

You can use your Mempool Explorer configuration to apply filters to Blocknative SDK. To do this, you can use the Export current configuration link in the Configurations Menu to download your current configuration files, and then use them to send a configuration to Blocknative SDK. You can read more on this feature on the SDK docs.

Explore Sample Feeds

To quickly get a sense of the types of feeds you can build with Mempool Explorer, we’ve created a couple of samples for you:

Share Your Mempool Explorer Feed

Blocknative allows you to easily share the feed you have created. Click on the “Share” button to copy a shortened version of the URL that includes all of the filters and display options you have selected.

You can also copy the event data in Mempool Explorer using the "Copy" button and easily share that with your team.


For detailed information about the event payload and its properties, please check out our API docs.

Supported Networks

Mempool Explorer supports the following Ethereum networks:

  • main

  • ropsten

  • rinkeby

  • goerli

  • kovan

  • xdai

We're working to add support for the Bitcoin Network. If there are any other networks that you would need, please feel free get in touch.


If you have any questions about Mempool Explorer, join our discord.