> ## Documentation Index
> Fetch the complete documentation index at: https://docs.uniblock.dev/llms.txt
> Use this file to discover all available pages before exploring further.
# getBlockHeader
> Retrieves detailed metadata for a specific TON block header, including identifiers, state flags, and timing information.
### Parameters
Unique identifier for a blockchain network.
Request identifier used to match responses.
JSON-RPC version.
JSON-RPC method name.
TON block header lookup request.
Parameters for getBlockHeader:
params.workchain: Block workchain ID. The masterchain uses -1.params.shard: Block shard ID encoded as a signed 64-bit integer string. The masterchain shard is -9223372036854775808.params.seqno: Sequence number of the block to retrieve.params.root\_hash: Optional block root hash. Providers may use this to disambiguate or validate the requested block.params.file\_hash: Optional block file hash. Providers may use this to disambiguate or validate the requested block.
### Returns
TON block header metadata.
TON object type marker.
TON extended block identifier.
TON object type marker.
Block workchain ID. The masterchain uses -1.
Block shard ID encoded as a signed 64-bit integer string.
Block sequence number.
Block root hash.
Block file hash.
TON network global ID.
Block header version.
Block header flags bitset.
Whether the block was created after a shard merge.
Whether the block was created after a shard split.
Whether the block precedes a shard split.
Whether the shard wants to merge.
Whether the shard wants to split.
Short hash of the validator list.
Catchain sequence number.
Minimum referenced masterchain sequence number.
Whether this block is a key block.
Previous key block sequence number.
Start logical time for this block.
End logical time for this block.
Unix timestamp when the block was generated.
Vertical sequence number.
Previous block identifiers.
TON extended block identifier.
TON object type marker.
Block workchain ID. The masterchain uses -1.
Block shard ID encoded as a signed 64-bit integer string.
Block sequence number.
Block root hash.
Block file hash.
Provider-specific response metadata.
```bash Curl theme={null}
curl --request POST \
--url https://api.uniblock.dev/uni/v1/json-rpc?chainId=toncoin \
--header 'content-type: application/json' \
--data '{
"id": 1,
"jsonrpc": "2.0",
"method": "getBlockHeader",
"params": {
"workchain": -1,
"shard": "-9223372036854775808",
"seqno": 39064985
}
}'
```
```json Success theme={null}
{
"jsonrpc": "2.0",
"id": 1,
"result": {}
}
```