> For the complete documentation index, see [llms.txt](https://docs.vechain.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.vechain.org/core-concepts/evm-compatibility/test-coverage/chain_id.md).

# Chain id

## Description

In the VeChain EVM, the `block.chainid` opcode returns the 32-byte genesis block ID, which represents a significantly larger value than the typical `chainId` used in other EVM-compatible networks.

This difference will cause the `eip712Domain` hex values of the contract and the local computation in the EIP712 test cases to be different.

Therefore, we modified the test code. When calculating the `eip712Domain` locally, instead of directly using the value returned by the `eth_chainId` RPC interface, we used `eth_getBlockByNumber` to obtain the ID of the genesis block to ensure that the hex value of `eip712Domain` is the same.

## Contracts Affected

| Contract Name |
| ------------- |
| ERC712        |


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