Tools · no sign-up
Smart contract tools
Small tools for reading smart contracts: paste an ABI or a signature and get the hashes the chain actually uses. Everything runs in your browser, nothing is sent anywhere, and each result links to a ready-made alert rule.
Tools
Pick a tool
Each runs in your browser: nothing you paste leaves your device.
Topic0 and selector calculator
A signature in, its topic0 and 4-byte selector out. Or paste a hash to see which event it is.
Open
ABI explorer
Paste an ABI, see every event, function and error with its topic0 or selector.
Open
Calldata decoder
Input data in, the function and its arguments out. Flags unlimited approvals before you sign.
Open
Event log decoder
A log's topics and data in, the event and its named arguments out.
Open
Calldata encoder
A signature and its arguments in, the ABI-encoded calldata out.
Open
Event signatures
Standard event signatures with their topic0, indexed arguments and the alerts that use them.
Open
FAQ
Frequently asked questions
Are the tools free?
Yes. They run in your browser, need no account and have no usage limit.
Do the tools read the blockchain?
No. They work on what you paste: an ABI, a signature or a hash. To follow what a contract does on chain, set up an alert, or see the live trackers.
How do these tools connect to alerts?
Every event a tool finds links to its catalog page, and each catalog page lists ready-made rules that alert you when a contract emits that event.
From an event signature to an alert
The Beta plan is free: one wallet and one contract, no credit card.