debug_traceBlockByHash

debug_traceBlockByHash re-executes an entire Base block and returns opcode-level execution traces for every transaction it contains, keyed off the block's hash rather than its number. Base is Coinbase's OP Stack optimistic rollup with roughly two-second blocks from its sequencer; gas is paid in ETH and the chain settles to Ethereum L1. Send the request to https://base.therpc.io/YOUR_API_KEY (chain ID 8453, hex 0x2105), pass the 32-byte block hash plus an optional tracer config, and the node replays each transaction against the parent state and hands back one trace per transaction in block order. Using the hash makes the target unambiguous even when a number could point at more than one block during a reorg.

Use cases

• Deterministically trace one exact Base block when you only have its hash — for example a hash captured during a reorg investigation where the block number alone would be ambiguous.
• Audit every internal call within a specific side-chain or replaced block on Base after a reorg, to see what execution the canonical chain discarded.
• Build a block-level call graph for MEV analysis on Base by running callTracer over the whole block and stitching the per-transaction call trees together.

Parameters

Response

Example request

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

Try it live in the Base playground.

Errors & troubleshooting

Common pitfalls

• This call carries the same cost as debug_traceBlockByNumber — it replays every transaction in the block, so a dense Base block is far heavier than tracing a single transaction.
• Tracing any historical Base block needs an archive node; a pruned node lacks the parent state and returns "block not found".
• A Base block packed with complex DEX or consumer-app transactions can exceed the default trace timeout on a remote node — narrow the tracer (e.g. callTracer) or raise the timeout in the options object.

Supported networks

• Mainnet — Chain ID: 8453
• Sepolia — Chain ID: 84532

See also

• debug_traceBlockByNumber
• debug_traceBlock
• debug_traceTransaction
• trace_block

1curl https://base.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H 'Content-Type: application/json' \
4  -d '{"jsonrpc":"2.0","id":1,"method":"debug_traceBlockByHash","params":["0x0000000000000000000000000000000000000000000000000000000000000000",{}]}'