# Blocks

Atlas/UBDM employs the universal concept of blocks which have the following fields in the response for the **Blocks** endpoint:

| Field                  | Description                                                                                                                                                                           |
| ---------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| block\_hash            | Hash of the block (unique per block)                                                                                                                                                  |
| parent\_block\_hash    | Hash of the parent block (set to a string of 65 zeros for Genesis blocks)                                                                                                             |
| height                 | Height of the block (number of confirmed blocks since Genesis block)                                                                                                                  |
| consensus\_time        | [Consensus timestamp](https://gitlab.com/coinmetrics/front-end/knowledge-base/-/blob/master/docs/on-chain-data/atlas-overview.md#consensus-timestamp); always increases monotonically |
| miner\_time            | [Miner/producer timestamp](https://gitlab.com/coinmetrics/front-end/knowledge-base/-/blob/master/docs/on-chain-data/atlas-overview.md#miner-timestamps)                               |
| nonce                  | Nonce of the block (hex-encoded)                                                                                                                                                      |
| extra\_data            | Extra data of the block (hex-encoded).                                                                                                                                                |
| n\_transactions        | Number of transactions                                                                                                                                                                |
| n\_balance updates     | Number of balance updates                                                                                                                                                             |
| version                | Version of the block                                                                                                                                                                  |
| difficulty             | Difficulty of the block                                                                                                                                                               |
| physical\_size         | The physical size of a block in bytes                                                                                                                                                 |
| consensus\_size        | The stripped size of the block with Segregated Witness (signature) data                                                                                                               |
| consensus\_size\_limit | The size limit of a block in weight units                                                                                                                                             |
| stale                  | Indicator if the block is stale.                                                                                                                                                      |