# web3

The `web3` namespace provides utility methods that are part of the standard Ethereum JSON-RPC API. These methods offer basic functionality for client identification and cryptographic operations. In Erigon, the web3 namespace is implemented through the `Web3API` interface and `Web3APIImpl` struct. The web3 namespace is enabled by default in Erigon's RPC daemon and provides essential utility functions that many Ethereum applications rely on for basic operations.

For API usage refer to the below official resources:

{% embed url="<https://ethereum.org/en/developers/docs/apis/json-rpc/>" %}

### Implementation Details

* The web3 namespace is implemented in `Web3APIImpl` which extends `BaseAPI` and uses the `ethBackend` for client version information
* The `web3_sha3` method uses Erigon's crypto library implementation of Keccak-256, which is the same hashing algorithm used throughout Ethereum
* Both methods are lightweight utility functions that don't require complex blockchain state access

### Usage Considerations

* `web3_clientVersion` is often used by applications to identify the Ethereum client type and version for compatibility checks
* `web3_sha3` provides the same Keccak-256 hashing that's used for Ethereum addresses, transaction hashes, and other cryptographic operations in the protocol
* These methods are part of the core Ethereum JSON-RPC specification and are supported by all major Ethereum clients

### Availability

* The web3 namespace is enabled by default in Erigon's RPC daemon
* No special configuration is required to use these methods
* They are available on both HTTP and WebSocket connections