isBlockhashValid - Solana

Example code for the isBlockhashValid JSON-RPC method. Complete guide on how to use the isBlockhashValid JSON-RPC method in the GetBlock Web3 documentation.

This method reports whether a blockhash is still recent enough to be accepted by the cluster. Blockhashes expire roughly 150 slots after they are produced.

Parameters

Parameter	Type	Required	Description
blockhash	string	Yes	Base58-encoded blockhash to check
config	object	No	Configuration object controlling commitment

Config Object

Field	Type	Required	Description
commitment	string	No	Commitment level: processed, confirmed, or finalized. Defaults to finalized
minContextSlot	number	No	Minimum slot the request can be evaluated at

Request

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "isBlockhashValid",
    "params": ["9zJqLXK9pMhQZ4tGqVvUcxrKpKQ3pMSJ1nZmVeXtBqTd", {"commitment": "processed"}],
    "id": "getblock.io"
}'

@solana/web3.js

example.js

const { Connection } = require('@solana/web3.js');

const connection = new Connection('https://go.getblock.io/<ACCESS-TOKEN>/', 'processed');

const isValid = await connection.isBlockhashValid('9zJqLXK9pMhQZ4tGqVvUcxrKpKQ3pMSJ1nZmVeXtBqTd');

console.log(isValid);

Request

example.py

import requests

response = requests.post(
    'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers={'Content-Type': 'application/json'},
    json={
        'jsonrpc': '2.0',
        'method': 'isBlockhashValid',
        'params': ["9zJqLXK9pMhQZ4tGqVvUcxrKpKQ3pMSJ1nZmVeXtBqTd", {"commitment": "processed"}],
        'id': 'getblock.io'
    }
)

print(response.json()['result'])

Rust

example.rs

use reqwest::Client;
use serde_json::{json, Value};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();

    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&json!({
            "jsonrpc": "2.0",
            "method": "isBlockhashValid",
            "params": ["9zJqLXK9pMhQZ4tGqVvUcxrKpKQ3pMSJ1nZmVeXtBqTd", {"commitment": "processed"}],
            "id": "getblock.io"
        }))
        .send()
        .await?
        .json::<Value>()
        .await?;

    println!("Result: {}", response["result"]);
    Ok(())
}

Response

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": {
        "context": {
            "slot": 397234561
        },
        "value": true
    }
}

Response Parameters

Parameter	Type	Description
jsonrpc	string	JSON-RPC protocol version ("2.0")
id	string	Request identifier matching the request
result	object	RPC response object where value is true when the blockhash is still valid

Use Cases

• Pre-Send Checks: Avoid submitting a transaction built on an expired blockhash

• Retry Loops: Stop rebroadcasting once the referenced blockhash expires

• Offline Signing: Validate a blockhash after a delay between signing and submission

• Queue Draining: Discard queued transactions whose blockhashes have lapsed

Error Handling

Error Code	Message	Description
-32602	Invalid params	Blockhash is not valid base58 or has the wrong length
-32603	Internal error	Node failed to read the blockhash queue