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

Response

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

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

See also

• eth_getBlockByNumber
• eth_getBlockReceipts
• eth_getTransactionByHash
• eth_getBlockTransactionCountByHash

1curl https://ethereum.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H 'Content-Type: application/json' \
4  -d '{"jsonrpc":"2.0","id":1,"method":"eth_getBlockByHash","params":["",""]}'