New blocks — `blocks`

Subscribe to the blocks channel to receive an event for every new block. By default you get a compact summary; add full: true to receive the entire block instead. No address required.

{ "action": "subscribe", "channel": "blocks" }
{ "action": "subscribe", "channel": "blocks", "full": true }

`block` — summary

{
  "type": "block",
  "data": {
    "height": 840002,
    "hash": "0000...abc",
    "previous_hash": "0000...def",
    "num_txs": 2841
  }
}

Field	Type	Description
`type`	string	Always `"block"`.
`data.height`	integer	Block height.
`data.hash`	string	Block hash.
`data.previous_hash`	string	Previous block's hash.
`data.num_txs`	integer	Number of transactions in the block.

`block_full` — full block (`full: true`)

With full: true you receive the entire block: every transaction, every input with the output it spends already resolved, and every output.

High volume

The full block carries every transaction in the block. Subscribe with full: true only if you genuinely need them all — to follow a specific address use balance or history instead.

{
  "type": "block_full",
  "data": {
    "height": 840002,
    "hash": "0000...abc",
    "previous_hash": "0000...def",
    "num_txs": 2841,
    "tx": [
      {
        "block_n": 0,
        "txid": "e3b0c4...",
        "vin": [
          { "txid": "e3b0c4...", "n": 0, "prev_txid": "0000...0000", "prev_n": 0, "prev_out": null }
        ],
        "vout": [
          { "txid": "e3b0c4...", "n": 0, "amount": "625000000" }
        ]
      },
      {
        "block_n": 1,
        "txid": "4a5e1e...",
        "vin": [
          {
            "txid": "4a5e1e...",
            "n": 0,
            "prev_txid": "1f3c2b...",
            "prev_n": 2,
            "prev_out": { "txid": "1f3c2b...", "n": 2, "amount": "70000" }
          }
        ],
        "vout": [
          { "txid": "4a5e1e...", "n": 0, "amount": "50000" },
          { "txid": "4a5e1e...", "n": 1, "amount": "19000" }
        ]
      }
    ]
  }
}

data — height, hash, previous_hash, num_txs (as in the summary), plus tx (the transactions).

Transaction (each item of tx)

Field	Type	Description
`block_n`	integer	Position of the transaction within the block (`0` = coinbase).
`txid`	string	Transaction id.
`vin`	array	Inputs (see below).
`vout`	array	Outputs (see below).

Input (each item of vin)

Field	Type	Description
`txid`	string	Id of the transaction this input belongs to.
`n`	integer	Index of this input.
`prev_txid`	string	Transaction of the output being spent. All-zero for coinbase.
`prev_n`	integer	Output index being spent.
`prev_out`	object \| `null`	The output being spent, resolved (fields below). `null` for coinbase.

Output (each item of vout, and prev_out)

Field	Type	Description
`txid`	string	Transaction that created the output.
`n`	integer	Output index within that transaction.
`amount`	string	Value in the smallest unit (satoshis), as a string.

block — summary​

block_full — full block (full: true)​

`block` — summary

`block_full` — full block (`full: true`)