eth_newPendingTransactionFilter

eth_newPendingTransactionFilter creates a server-side filter that watches for incoming pending transactions on Base — Coinbase's OP Stack rollup where gas is paid in ETH — and returns a hex filter ID. Polling that ID with eth_getFilterChanges returns the hashes of transactions that entered the node's mempool since your last poll. On Base, transactions flow to the sequencer for ordering, and the ~2s block time means pending hashes move into blocks quickly. Create the filter against https://base.therpc.io/YOUR_API_KEY (Base mainnet, chain ID 8453 / 0x2105); it takes no parameters.

Use cases

• Watch the Base mempool for pending transactions and, after fetching each one with eth_getTransactionByHash, react to those from a specific sender address.
• Build a live gas-price tracker by sampling the maxPriorityFeePerGas and maxFeePerGas of pending transactions to gauge current tip pressure on Base before you submit your own.

Parameters

此方法不需要任何参数，传入空数组 [] 即可。

Response

Example request

1curl https://base.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "eth_newPendingTransactionFilter",
7    "params": [],
8    "id": 1
9  }'

Try it live in the Base playground.

Errors & troubleshooting

Common pitfalls

• Each poll returns only transaction hashes; call eth_getTransactionByHash to retrieve the full transaction details for any hash you care about.
• A pending transaction on Base may never be included — it can be dropped or replaced by a same-nonce transaction with a higher fee — so never treat a pending hash as confirmed; wait for a receipt.
• During heavy consumer-app and DEX activity the Base mempool can flood a single poll with thousands of hashes; for sustained real-time use prefer a WebSocket eth_subscribe("newPendingTransactions") stream over repeated filter polling.

Supported networks

• Mainnet — Chain ID: 8453
• Sepolia — Chain ID: 84532

See also

• eth_getFilterChanges
• eth_uninstallFilter
• eth_newFilter
• eth_subscribe

1curl https://base.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H 'Content-Type: application/json' \
4  -d '{"jsonrpc":"2.0","id":1,"method":"eth_newPendingTransactionFilter","params":[]}'