eth_getBlockByNumber

Returns information about a block by its number.

Flashblocks: Query https://mainnet.base.org with "pending" to fetch the live Flashblock in progress — a real block object updated every ~200ms with new pre-confirmed transactions. The response shape is identical; the block is simply not yet sealed.

Parameters

string

required

Block number in hex, or "latest", "pending", "safe", "finalized", "earliest". Use "pending" to get the in-progress block.

boolean

required

If true, returns full transaction objects. If false, returns only transaction hashes.

Returns

object

A block object, or null if no block was found.

Show Block Fields

string

Block number in hex. null when pending.

string

Block hash. null when pending.

string

Hash of the parent block.

string

PoW nonce. Always "0x0000000000000000" on Base (PoS).

string

Hash of the uncles list. Always empty on Base.

string

Bloom filter for the block’s logs.

string

Root of the transaction trie.

string

Root of the final state trie.

string

Root of the receipts trie.

string

Address of the fee recipient (coinbase).

string

Always "0x0" on Base (PoS).

string

Present in all blocks; repurposed for PoS consensus (bytes32 hex).

string

Arbitrary data field set by the sequencer.

string

Block size in bytes (hex).

string

Maximum gas allowed in this block (hex).

string

Total gas used in this block (hex).

string

Unix timestamp (hex).

string

Optional. Unix timestamp in milliseconds (hex). Present on networks where Denim is active; omitted when the block’s BaseTime metadata is unavailable. See Denim Millisecond Timestamps.

array

Array of transaction hashes or full transaction objects.

array

Always [] on Base.

array

Always [] on Base.

string

Merkle root of the withdrawals list (EIP-4895, bytes32 hex).

string

EIP-1559 base fee per gas (hex).

string

Total blob gas used (EIP-4844, hex).

string

Excess blob gas for blob fee calculation (EIP-4844, hex).

string

Parent beacon block root (EIP-4788).

string

Hash of requests (EIP-7685).

Flashblock-Specific Response Fields

When querying "pending", the response is a live snapshot of the block being built. A few fields behave differently:

Field	Standard `latest`	Flashblocks `pending`
`number`	Sealed block number	Current block number (being built)
`hash`	Final block hash	Hash of the partial block at this Flashblock index
`gasUsed`	Final gas used	Cumulative gas used up to this Flashblock
`transactions`	All sealed transactions	Transactions pre-confirmed so far
`blobGasUsed`	Final blob gas used	Propagated from cumulative Flashblock state

Denim Millisecond Timestamps

Denim is live on Base Sepolia. On Base Mainnet, this behavior applies once Denim activates. See the Denim overview for activation status.

With Denim active, the block object adds an optional timestampMs field: a JSON-RPC quantity containing the full Unix timestamp in milliseconds. The existing timestamp field stays in Unix seconds. The response omits timestampMs when the block’s BaseTime metadata has been pruned or is otherwise unavailable. See 200ms Blocks for the full list of affected methods.

Example

curl https://mainnet.base.org \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getBlockByNumber",
    "params": ["latest", false],
    "id": 1
  }'

curl https://mainnet.base.org \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getBlockByNumber",
    "params": ["pending", false],
    "id": 1
  }'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "baseFeePerGas": "0x4c4b40",
    "blobGasUsed": "0x5384cc",
    "difficulty": "0x0",
    "excessBlobGas": "0x0",
    "extraData": "0x01000000640000000500000000004c4b40",
    "gasLimit": "0x17d78400",
    "gasUsed": "0x2155bc7",
    "hash": "0x491bca01d4bc076d60833dbd973fe031a74e7ae31866bf70d077619e09edb6ff",
    "logsBloom": "0xb765d5b0...",
    "miner": "0x4200000000000000000000000000000000000011",
    "mixHash": "0x47aecef0e1afa26b8e1f428e9a8696cf53d85c62587d8c2cea079c715cd29626",
    "nonce": "0x0000000000000000",
    "number": "0x2c31b0b",
    "parentBeaconBlockRoot": "0x15b9e7c8ac4cbe92dafc849ed30a23e91624bbe5cbe199c0ccea3f7de7fc6d49",
    "parentHash": "0x89f4c9e23a2f706f0afa9ca8f770c4b7dcbcb73ba7e9b1c29c4a8c1b90c31d24",
    "receiptsRoot": "0x5a428d77344334537d7adaf85a45eb6d7977bc807a68c669f36cb043600da6d2",
    "requestsHash": "0xe3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
    "sha3Uncles": "0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347",
    "size": "0x1bb3b",
    "stateRoot": "0x1b1525af0cdd504147b89f2a7ce1838ccb70c5439c45ce55522c2e2529801e87",
    "timestamp": "0x6a1092f9",
    "transactions": [
      "0x03c8f106f18ad94190e763e21b584c5825b2f4c61f1274c0e8abe65b4476cd51",
      "..."
    ],
    "transactionsRoot": "0x6b9c9fcbdf98a8f4d38a3c16d099e9f0c7b7b474c2f5e044af7c91949c04a234",
    "uncles": [],
    "withdrawals": [],
    "withdrawalsRoot": "0x57f4414a70a4af5e1a97b5fd8b8c6c870c00e8d9dbc0fde0059ce46e2cd28e5b"
  }
}

Overview

CLIs

Base Chain API

Tokenized Stocks API

Base Verify API

Migrated Documentation

Parameters

Returns

Flashblock-Specific Response Fields

Denim Millisecond Timestamps

Example

​Parameters

​Returns

​Flashblock-Specific Response Fields

​Denim Millisecond Timestamps

​Example

Parameters

Returns

Flashblock-Specific Response Fields

Denim Millisecond Timestamps

Example