Overview
Flashblocks is a transaction preconfirmation feature on Base that delivers partial block updates every 200 milliseconds, achieving up to 10x faster confirmations than Base’s standard 2-second block time. This enables applications to access near-instant transaction feedback, enhancing responsiveness for time-critical use cases like decentralized exchanges and onchain gaming.
Flashblocks is useful for:
- Applications that require real-time feedback
- Decentralized exchanges and trading platforms
- Onchain games or apps with frequent state updates
- Interfaces that benefit from faster feedback such as live dashboards
Using Flashblocks with Base Endpoints
Flashblocks is currently supported on the Base and can be accessed using your existing Quicknode Base endpoint — no additional add-ons are required.
| Network | Flashblocks Availability |
|---|---|
| Base Mainnet | ✅ |
| Base Sepolia | ✅ |
Supported RPC Methods
Access Flashblocks preconfirmations through your Base endpoint by using the pending tag on methods like eth_call, eth_estimateGas, eth_getBlockByNumber, eth_getBalance, and eth_getTransactionCount. Additionally, fetch Flashblocks related transaction details via methods such as eth_getTransactionReceipt, eth_getTransactionByHash, and eth_simulateV1. You can also use eth_subscribe over WebSocket to stream real-time Flashblock data including new transactions, pending logs, and block state updates, and stop active streams when needed using eth_unsubscribe.
| Method | Description |
|---|---|
eth_call | With "pending", executes a call against the latest Flashblock |
eth_estimateGas | With "pending", estimates gas usage against the latest Flashblock |
eth_getBalance | With "pending", reflects balances from the latest Flashblock |
eth_getBlockByNumber | With "pending", returns the most recent Flashblock |
eth_getLogs | With "pending", returns logs from the latest Flashblock |
eth_getTransactionByHash | Returns the transaction with the specified hash |
eth_getTransactionCount | With "pending", returns the updated nonce from Flashblocks |
eth_getTransactionReceipt | Returns receipts for preconfirmed transactions |
eth_simulateV1 | Simulates transactions against the latest Flashblock state |
eth_subscribe | Subscribes to real-time Flashblock events via WebSocket (e.g., newFlashblocks, newFlashblockTransactions, pendingLogs) |
eth_unsubscribe | Unsubscribes from an active WebSocket subscription created with eth_subscribe |