> ## Documentation Index
> Fetch the complete documentation index at: https://daehan-base.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.
# eth_getBlockByNumber
> Returns block information by number. On Flashblocks endpoints, the pending tag returns the live pre-confirmed block updated every ~200ms.
Returns information about a block by its number.
**Flashblocks:** Query `https://mainnet-preconf.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
Block number in hex, or `"latest"`, `"pending"`, `"safe"`, `"finalized"`, `"earliest"`. Use `"pending"` on a Flashblocks endpoint to get the in-progress block.
If `true`, returns full transaction objects. If `false`, returns only transaction hashes.
## Returns
A block object, or `null` if no block was found.
Block number in hex. `null` when pending.
Block hash. `null` when pending.
Hash of the parent block.
PoW nonce. Always `"0x0000000000000000"` on Base (PoS).
Hash of the uncles list. Always empty on Base.
Bloom filter for the block's logs.
Root of the transaction trie.
Root of the final state trie.
Root of the receipts trie.
Address of the fee recipient (coinbase).
Always `"0x0"` on Base (PoS).
Always `"0x0"` on Base (PoS).
Arbitrary data field set by the sequencer.
Block size in bytes (hex).
Maximum gas allowed in this block (hex).
Total gas used in this block (hex).
Unix timestamp (hex).
Array of transaction hashes or full transaction objects.
Always `[]` on Base.
Always `[]` on Base.
EIP-1559 base fee per gas (hex).
Total blob gas used (EIP-4844, hex).
Excess blob gas for blob fee calculation (EIP-4844, hex).
Parent beacon block root (EIP-4788).
Hash of requests (EIP-7685).
## Flashblock-Specific Response Fields
When querying `"pending"` on a Flashblocks endpoint, 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 |
## Example
```bash Standard (latest sealed block) theme={null}
curl https://mainnet.base.org \
-X POST \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"method": "eth_getBlockByNumber",
"params": ["latest", false],
"id": 1
}'
```
```bash Flashblocks (pending, live at ~200ms) theme={null}
curl https://mainnet-preconf.base.org \
-X POST \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"method": "eth_getBlockByNumber",
"params": ["pending", false],
"id": 1
}'
```
```json Response theme={null}
{
"jsonrpc": "2.0",
"id": 1,
"result": {
"number": "0x158a0e9",
"hash": "0x5c330e55a190f82ea486b61e5b12e27dfb4fb3cecfc5746886ef38ca1281bce8",
"parentHash": "0x9edc29b8b0a1e31d28616e40c16132ad0d58faa8bb952595b557526bdb9a960a",
"timestamp": "0x67bf8332",
"gasLimit": "0x3938700",
"gasUsed": "0xab3f",
"baseFeePerGas": "0xfa",
"transactions": ["0x7ef8f8a0..."],
"withdrawals": [],
"miner": "0x4200000000000000000000000000000000000011"
}
}
```