eth_getBlockByHash

eth_getBlockByHash returns the full block data for the Avalanche C-Chain block identified by a given 32-byte hash — header fields, gas metrics, AVAX-denominated base fee, and either transaction hashes or full transaction objects. It is the hash-keyed companion to eth_getBlockByNumber, useful when you already hold a block hash and want a definite, reorg-proof reference. Send the hash to https://avalanche.therpc.io/YOUR_API_KEY (chain ID 43114); an unknown hash returns null.

Use cases

• Fetch full block data when you already hold a specific hash — for example the blockHash from a C-Chain transaction receipt.
• Detect reorganisations by comparing a stored hash against what the node now returns for that height; under Snowman finality on the C-Chain this is rare but worth guarding.
• Retrieve gas metrics, the AVAX base fee, timestamp, and other header fields for a specific canonical block, cross-referenced with Snowtrace.

Parameters

Response

Example request

1curl https://avalanche.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 Avalanche playground.

Errors & troubleshooting

Common pitfalls

• Pass a real boolean for includeTransactions, not the string "true" — JSON-RPC requires the actual boolean type or the request is rejected.
• With includeTransactions=true, a busy C-Chain block can exceed 1 MB; stream or paginate if bandwidth is tight.
• An unknown hash yields null, not an error — always null-check the result before reading fields.

Supported networks

• Mainnet — Chain ID: 43114
• Fuji

See also

• eth_getBlockByNumber
• eth_getBlockReceipts
• eth_getTransactionByHash
• eth_getBlockTransactionCountByHash

1curl https://avalanche.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":["",""]}'