eth_chainId - Astar RPC Method
Get the chain ID for Astar. Essential for transaction signing and network verification.
Returns the chain ID used for transaction signing on Astar.
Why Astar? Build on Polkadot's leading dApp hub supporting EVM, WASM, and upcoming PolkaVM environments with EVM + WASM + PolkaVM support, Build2Earn developer rewards, dApp Staking, and Soneium cross-layer integration.
Use Cases
The eth_chainId method is essential for:
- Transaction signing - Ensure transactions are signed for the correct network
- Network verification - Confirm connection to the expected chain
- Multi-chain apps - Handle different networks programmatically
- Wallet integration - Validate network before transactions
Code Examples
Related Methods
net_version- Get network versioneth_syncing- Check sync status
eth_newPendingTransactionFilter
Create a filter for pending transaction notifications on Astar. Essential for mempool monitoring, transaction tracking, and MEV opportunity detection for cross-chain DeFi, multi-VM smart contracts, and XCM-enabled interoperability with Ethereum and Cosmos.
eth_syncing
Check the sync status of your Astar node. Returns sync progress or false when fully synced — essential for node health monitoring and dApp reliability.