> ## 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.

# lookupBlock | TON v2

> The lookupBlock method retrieves detailed information about a specific block in the TON blockchain. Use it on TON v2 via Chainstack.

The `lookupBlock` method retrieves detailed information about a specific block in the TON blockchain. This method allows you to query block data by specifying the workchain, shard, and sequence number of the block.

<Note>
  **TON billing: full or archive by block age**

  This method is billed as archive (2 RUs) when the requested block is 128 or more seqno behind the tip, and full (1 RU) otherwise. See [Request units — TON method scope](/docs/request-units#ton-method-scope).
</Note>

## JSON-RPC example

```shell Shell theme={"system"}
curl -X POST \
  'https://ton-mainnet.core.chainstack.com/f2a2411bce1e54a2658f2710cd7969c3/api/v2/jsonRPC' \
  -H 'Content-Type: application/json' \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "lookupBlock",
    "params": {
      "workchain": -1,
      "shard": "-9223372036854775808",
      "seqno": 39064874
    }
  }'
```

## Parameters

* `workchain` (integer, required) — The ID of the workchain. Example: `-1` for the masterchain.
* `shard` (string, required) — The ID of the shard. Example: `"-9223372036854775808"` for the masterchain.
* `seqno` (integer, required) — The sequence number of the block. Example: `39064874`.

## Response

* `id` (object) — The identifier of the block, containing:
  * `workchain` (integer) — The workchain ID of the block.
  * `shard` (string) — The shard ID of the block.
  * `seqno` (integer) — The sequence number of the block.
  * `root_hash` (string) — The root hash of the block.
  * `file_hash` (string) — The file hash of the block.
* `status` (integer) — The status of the block.
* `global_id` (integer) — The global ID of the block.
* `version` (integer) — The version of the block.
* `after_merge` (boolean) — Whether the block was created after a merge.
* `before_split` (boolean) — Whether the block was created before a split.
* `want_merge` (boolean) — Whether the block wants to merge.
* `want_split` (boolean) — Whether the block wants to split.
* `gen_utime` (integer) — The generation time of the block.
* `start_lt` (string) — The start logical time of the block.
* `end_lt` (string) — The end logical time of the block.

## Use case

A possible use case for the `lookupBlock` method in TON is for blockchain explorers, analytical tools, or any application that needs detailed information about specific blocks. This method can be used to:

1. Display detailed block information in a block explorer.
2. Analyze block characteristics for research or optimization purposes.
3. Verify block properties in custom validation processes.
4. Track the evolution of the blockchain by examining block metadata over time.


## OpenAPI

````yaml openapi/ton_node_api/v2/lookupBlock.json GET /lookupBlock
openapi: 3.0.0
info:
  title: lookupBlock example
  version: 1.0.0
  description: >-
    This is an API example for lookupBlock, a method to retrieve information
    about a specific block in the TON blockchain.
servers:
  - url: >-
      https://ton-mainnet.core.chainstack.com/f2a2411bce1e54a2658f2710cd7969c3/api/v2
security: []
paths:
  /lookupBlock:
    get:
      tags:
        - TON Operations
      summary: lookupBlock
      operationId: lookupBlock
      parameters:
        - name: workchain
          in: query
          required: true
          description: The workchain ID
          schema:
            type: integer
            default: -1
          example: -1
        - name: shard
          in: query
          required: true
          description: The shard ID
          schema:
            type: string
            default: '-9223372036854775808'
          example: '-9223372036854775808'
        - name: seqno
          in: query
          required: true
          description: The sequence number of the block
          schema:
            type: integer
            default: 39064874
          example: 39064874
      responses:
        '200':
          description: Information about the specified block
          content:
            application/json:
              schema:
                type: object
                properties:
                  id:
                    type: object
                    properties:
                      workchain:
                        type: integer
                        description: The workchain ID of the block
                      shard:
                        type: string
                        description: The shard ID of the block
                      seqno:
                        type: integer
                        description: The sequence number of the block
                      root_hash:
                        type: string
                        description: The root hash of the block
                      file_hash:
                        type: string
                        description: The file hash of the block
                  status:
                    type: integer
                    description: The status of the block
                  global_id:
                    type: integer
                    description: The global ID of the block
                  version:
                    type: integer
                    description: The version of the block
                  after_merge:
                    type: boolean
                    description: Whether the block was created after a merge
                  before_split:
                    type: boolean
                    description: Whether the block was created before a split
                  want_merge:
                    type: boolean
                    description: Whether the block wants to merge
                  want_split:
                    type: boolean
                    description: Whether the block wants to split
                  gen_utime:
                    type: integer
                    description: The generation time of the block
                  start_lt:
                    type: string
                    description: The start logical time of the block
                  end_lt:
                    type: string
                    description: The end logical time of the block

````