> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chainstack.com/llms.txt
> Use this file to discover all available pages before exploring further.

# isBlockhashValid | Solana

> The Solana isBlockhashValid method checks whether a given blockhash is still valid. Available on Solana via Chainstack JSON-RPC nodes.

The Solana `isBlockhashValid` method checks whether a given blockhash is still valid.

This method is useful for determining if a previously fetched blockhash can still be used for transaction submission. It helps prevent the use of expired blockhashes, which would cause transactions to fail.

## Parameters

* `blockhash` — the blockhash to validate, as a base-58 encoded string.
* `commitment` — (optional) the level of commitment desired:
  * `processed` — the node has processed the block and the block may be on a fork.
  * `confirmed` — the block is confirmed by the cluster as not being on a fork.
  * `finalized` — the block is finalized by the cluster.

## Response

* `result` — a boolean indicating whether the blockhash is still valid:
  * `true` — the blockhash is valid and can be used for transaction submission.
  * `false` — the blockhash is no longer valid and should not be used.

## Use case

A practical use case for `isBlockhashValid` is in transaction retry logic. When a transaction fails due to network issues, an application can use this method to check if the original blockhash is still valid before retrying the transaction. If the blockhash is no longer valid, the application knows it needs to fetch a new blockhash before retrying.


## OpenAPI

````yaml openapi/solana_node_api/isBlockhashValid.json POST /83e0d6661ee0488e22e167c18818cb38
openapi: 3.0.0
info:
  title: isBlockhashValid example
  version: 1.0.0
  description: This is an API example for Solana's isBlockhashValid.
servers:
  - url: https://solana-mainnet.core.chainstack.com
security: []
paths:
  /83e0d6661ee0488e22e167c18818cb38:
    post:
      tags:
        - query
      summary: isBlockhashValid
      operationId: isBlockhashValid
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                id:
                  type: integer
                  default: 45
                jsonrpc:
                  type: string
                  default: '2.0'
                method:
                  type: string
                  default: isBlockhashValid
                params:
                  type: array
                  items:
                    anyOf:
                      - type: string
                        description: The blockhash to validate, as a base-58 encoded string
                        default: AspJzsEukGPuLYsebpUSSeS79GtYVVh6Bn4478qWXqBK
                      - type: object
                        properties:
                          commitment:
                            type: string
                            default: processed
                  default:
                    - AspJzsEukGPuLYsebpUSSeS79GtYVVh6Bn4478qWXqBK
                    - commitment: processed
      responses:
        '200':
          description: Blockhash validity status
          content:
            application/json:
              schema:
                type: object
                properties:
                  jsonrpc:
                    type: string
                  id:
                    type: integer
                  result:
                    type: boolean

````