Event Topic Calculator
Calculate event signature hashes (topic0) for Solidity events
1. What are Event Topics?
In Ethereum, events are stored in transaction logs. The first topic (topic0) is always the keccak256 hash of the event signature. This is used to filter and identify specific events.
2. How does it work?
Event Signature Format
Event signatures follow the format: EventName(type1,type2,...). Note that parameter names are omitted, only types are included. For example: Transfer(address,address,uint256)
3. Examples
ERC-20 Transfer event
Transfer(address,address,uint256)
→ 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3efERC-20 Approval event
Approval(address,address,uint256)
→ 0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925ERC-721 Transfer event
Transfer(address,address,uint256)
→ 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef