Account Abstraction Explorer
Decode ERC-4337 bundles: UserOperations, paymasters, gas per op, deployed smart accounts.
Try an example: Two UserOperations in one bundle (offline)
How it works
Decodes ERC-4337 EntryPoint v0.6/v0.7/v0.8 events in a bundle transaction — every UserOperation with its sender, paymaster sponsorship, success, gas cost and revert reason, plus newly deployed accounts and the bundler's margin. For a smart-account address it shows the code type, EIP-7702 delegation, EntryPoint nonces and deposits and the proxy implementation.
- EntryPoint events are matched by topic0 computed locally from the signatures UserOperationEvent(bytes32 indexed userOpHash, address indexed sender, address indexed paymaster, uint256 nonce, bool success, uint256 actualGasCost, uint256 actualGasUsed), UserOperationRevertReason, PostOpRevertReason and AccountDeployed.
- Known EntryPoints: v0.6 0x5FF137D4…2789, v0.7 0x00000000…a032 and v0.8 0x4337084D…f108 (deployed at the same address on every chain; checked with eth_getCode). Events from any other emitter are decoded but flagged.
- Bundler = the transaction sender (tx.from). Bundler margin = sum of actualGasCost charged to the UserOperations minus the transaction fee actually paid; it assumes the handleOps beneficiary is the bundler.
- Nonce = 192-bit key << 64 | 64-bit sequence (ERC-4337 semi-abstracted nonce). Revert data is decoded as Error(string)/Panic(uint256) or shown as a custom-error selector.
- Account mode: eth_getCode (0xef0100‖address = EIP-7702 delegation), eth_getBalance, EntryPoint.getNonce(account, 0) and balanceOf(account) (deposit) on each EntryPoint, and the Contract Upgrade Explorer for the proxy implementation.
For scripts and AI agents
- JSON API:
POST https://accountabstractionexplorer.usefulweb.site/api/v1/calculate(same calculation as this page) - Interface description: OpenAPI 3.1 · AI guide: llms.txt
- MCP server (Streamable HTTP):
https://accountabstractionexplorer.usefulweb.site/mcp· tool nameaccount_abstraction_explorer
Example request
curl -s -X POST https://accountabstractionexplorer.usefulweb.site/api/v1/calculate \
-H 'content-type: application/json' \
-d '{…see OpenAPI examples…}'Related tools
- Transaction Decoder – See what an EVM transaction actually did: call, events, token transfers, fee, finality.
- Smart Contract Upgrade Explorer – Is this smart contract upgradeable, who controls upgrades, and what changed?
- Gas Fee Intelligence Explorer – Live gas on 7 EVM chains: base fee, tips, trend and the USD cost of transfers and swaps.