eth_newPendingTransactionFilter

eth_newPendingTransactionFilter registers a server-side filter that watches for transactions entering the OP Mainnet mempool and returns a hex filter ID. Polling that ID with eth_getFilterChanges yields the hashes of pending transactions seen since your last poll. OP Mainnet is the ETH-gas OP Stack rollup at chain ID 10 (0xa), where a single sequencer orders transactions; the pending set you observe reflects what that sequencer has received but not yet sealed into a block. Create the filter against https://optimism.therpc.io/YOUR_API_KEY.

Use cases

• Watch the OP Mainnet mempool for incoming pending transactions and, after fetching each by hash, flag the ones from a sender address you care about.
• Build a live fee tracker by sampling the maxFeePerGas and maxPriorityFeePerGas of pending transactions to gauge what tips are landing inclusion on OP Mainnet right now.

Parameters

هذا الأسلوب لا يأخذ أي معاملات. مرر مصفوفة فارغة [].

Response

Example request

1curl https://optimism.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 Optimism playground.

Errors & troubleshooting

Common pitfalls

• Polling returns only transaction hashes — call eth_getTransactionByHash for each one to read the sender, value, gas fields, or calldata.
• A pending transaction may never be sealed by the sequencer or may be replaced by a same-nonce transaction with a higher fee; never treat a hash from this filter as confirmed — wait for a receipt via eth_getTransactionReceipt.
• During congestion the OP Mainnet mempool can flood each poll with thousands of hashes; for sustained real-time consumption a WebSocket eth_subscribe (newPendingTransactions) stream is more efficient than polling this filter.

Supported networks

• Mainnet — Chain ID: 10
• Sepolia — Chain ID: 11155420

See also

• eth_getFilterChanges
• eth_uninstallFilter
• eth_newFilter
• eth_subscribe

1curl https://optimism.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":[]}'