EXAMPLES

When you are connected to a local node:
cast chain-id
31337
When providing a RPC endpoint URL:
cast chain-id --rpc-url https://rpc.sepolia.org/
11155111
Works with -r too:
cast chain-id -r https://polygon-rpc.com
137

DOCUMENTATION

cast chain-id

NAME

cast-chain-id - Get the Ethereum chain ID.

SYNOPSIS

cast chain-id [options]

DESCRIPTION

Get the Ethereum chain ID from the RPC endpoint we are connected to.

OPTIONS

RPC Options

--rpc-url url
    The RPC endpoint. Accepts a URL or an existing alias in the [rpc_endpoints] table, like mainnet.     Environment: ETH_RPC_URL

Common Options

-h
--help
    Prints help information.

EXAMPLES

  1. Get the chain ID when talking to $RPC:

    cast chain-id --rpc-url $RPC

  2. Get the chain ID when $ETH_RPC_URL is set:

    cast chain-id

SEE ALSO

cast, cast chain