eth_getBlockByHash

eth_getBlockByHash returns the full block that matches a 32-byte hash on Ethereum mainnet. A block hash uniquely pins one block, so unlike a height it survives reorgs cleanly — the hash either exists in your view of the chain or it doesn't. The response carries the header (parent hash, timestamp, miner/proposer, state and receipts roots), the EIP-1559 baseFeePerGas, gas metrics, the post-Merge withdrawals list, and either full transaction objects or just their hashes depending on the second argument. Send it to https://ethereum.therpc.io/YOUR_API_KEY (chain ID 1, native coin ETH). An unknown hash yields null.

Use cases

Resolve a hash you already hold. A transaction receipt or a log entry hands you a blockHash; this turns it into the full block context.
Reorg detection. Store the hash you saw for a height, then later ask the node for that same height — if the canonical hash differs, that slot reorged and you reindex from there.
Pull header detail for one block. Read the validator withdrawals, gas used vs limit, base fee, and the various roots for a specific canonical block without scanning a range.

Parameters

#	Name	Type	Required	Description
1	`blockHash`	string (hex)	Yes	The hash of the block to retrieve.
2	`includeTransactions`	boolean	Yes	When true, transactions[] contains full transaction objects. When false, only hashes.

Response

Type	Description
object \| null	Block object with fields: number, hash, parentHash, timestamp, miner, gasUsed, gasLimit, baseFeePerGas, transactions, uncles, withdrawals, stateRoot, receiptsRoot, transactionsRoot, logsBloom, extraData, size, difficulty, totalDifficulty, mixHash, nonce, sha3Uncles. Returns null if no block was foun

Example request

1curl https://ethereum.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "eth_getBlockByHash",
7    "params": [
8        "0x0000000000000000000000000000000000000000000000000000000000000000",
9        false
10      ],
11    "id": 1
12  }'

Try it live in the Ethereum playground.

Errors & troubleshooting

Code	Message	Cause
`-32602`	`Invalid params`	Block hash is malformed or not 32 bytes.

Common pitfalls

The second argument is a real boolean. Passing the string "true" makes some nodes reject the request or treat it as false — send JSON true/false, not quoted text.
With the flag set to true, a full mainnet block packed with Uniswap and transfer activity can push the response past 1 MB. Stream or fetch hashes only and pull transactions on demand if bandwidth matters.
An unknown or non-canonical hash returns null, not an error. Null-check before reading .number or .transactions, or you'll throw on a missing block.

Supported networks

Mainnet — Chain ID: 1
Sepolia — Chain ID: 11155111