trace_replayTransaction

trace_replayTransaction replays a single historical transaction on Base and returns a selectable combination of call-tree trace, opcode-level VM trace, and state diff. Base is the OP Stack optimistic rollup Coinbase runs, paying gas in ETH and settling to Ethereum L1, so the replay uses the same OpenEthereum-style trace format other EVM trace clients produce. Send the transaction hash and a traceTypes array (trace, vmTrace, stateDiff, or any mix) to https://base.therpc.io/YOUR_API_KEY (chain ID 8453, hex 0x2105). The stateDiff output is the standout feature: it maps each affected address to its balance, nonce, code, and storage changes using =, +, -, and *{from,to} markers, giving you a precise before/after picture of what the transaction altered.

Use cases

• Reconstruct the exact storage changes a historical Base transaction caused, reading the stateDiff markers to see every slot it wrote, for forensic analysis.
• Debug a revert on a Base contract by examining the stateDiff and call tree together to pinpoint which storage slot or sub-call triggered the failure.
• Produce a complete audit trail of balance and storage changes for compliance, capturing ETH and token movements that left no event log.

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": "trace_replayTransaction",
7    "params": [
8        "0x0000000000000000000000000000000000000000000000000000000000000000",
9        [
10          "trace"
11        ]
12      ],
13    "id": 1
14  }'

Try it live in the Base playground.

Errors & troubleshooting

Common pitfalls

• Requesting vmTrace on a complex Base transaction produces enormous output; stick to trace or stateDiff when you do not need opcode-level detail.
• The method requires a trace-enabled archive node; a pruned Base node lacks the historical state needed to replay.
• The vmTrace format is Parity-specific — do not confuse it with Geth's debug_traceTransaction struct-log; tooling built for one will not parse the other.

Supported networks

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

See also

• trace_transaction
• trace_replayBlockTransactions
• trace_call
• debug_traceTransaction

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":"trace_replayTransaction","params":["0x0000000000000000000000000000000000000000000000000000000000000000",[]]}'