Polygonscan Event Log Filters by Address and Topic

Polygonscan event logs can be filtered through Etherscan API V2 by contract address, event topics and a selected range of Polygon PoS blocks. Set chainid=137 for mainnet, then use module=logs and action=getLogs with an Etherscan API key. The address selects the emitter; topics narrow matches by event signature or indexed parameter.

A wallet address inside a token event plays a different role from the contract that emitted it. Keeping those roles separate makes log searches useful for transfer analysis, application monitoring and reconciliation without confusing participants with emitters.

Contract Addresses Separate Emitters From Participants

The address filter scopes a query to a deployed contract on the selected network. A log’s address identifies its emitting contract. Sender and recipient addresses can appear among that event’s indexed parameters or non-indexed data. Their location follows the event declaration. A transaction that calls several contracts may contain logs with different emitting addresses, so its destination does not describe every log. Address-only searches retain the emitter’s different event types, which helps when the event of interest has not yet been identified.

Polygon PoS testnet requests use chainid=80002 ; those records belong to a different network from mainnet records queried with chainid=137 .

Event Definitions Fix Topic Positions

Event Signatures

A contract’s application binary interface (ABI) lists its events, parameter types and indexing. For a non-anonymous Solidity event, topic0 contains the Keccak-256 hash of its canonical event signature. The signature includes the event name and canonical parameter types in their declared order. Argument names and the indexed keyword are excluded. The event signature hash occupies 32 bytes; a function selector uses the first four bytes of its own signature hash. Anonymous events omit the signature topic, so topic0 then holds an indexed argument when one exists. Non-anonymous events can have up to three indexed parameters; anonymous events can have four.

Indexed Parameter Order

Indexed parameters occupy topic slots in their declared order. Non-indexed parameters go into data . Topic conditions cannot inspect those values; value-based filtering of non-indexed fields requires decoding the retrieved data.

Address Encoding

An indexed address uses a 32-byte topic value, with leading zero padding. A plain wallet address and its encoded topic are different representations. The event’s declared field position distinguishes an indexed sender from an indexed recipient.

Hashed Parameter Values

Indexed string and bytes values use Keccak-256 hashes of their contents. Arrays and structs follow the ABI’s special encoding rules before hashing. A hash can match a known input. An ABI decoder cannot recover the original value from that topic alone. A separate non-indexed copy remains readable when the event includes one.

Filter Combinations Balance Coverage and Specificity

Etherscan API V2 supports address-only, topic-only and combined log queries over a block range. These configurations answer different questions: the emitter identifies where a record originated, while topic positions specify which indexed values qualify. This comparison uses non-anonymous events wherever topic0 represents an event signature. Every configuration retains the request’s chain and block boundaries.

The topic0_1_opr parameter selects and or or between those positions. OR broadens the topic condition; it does not move a value between slots. Topic-only queries expose topic0 through topic3 , with pair operators such as topic1_2_opr . Each pair operator applies only when both corresponding topics are supplied.

Block Ranges and Pagination Define Export Coverage

Block boundaries define which part of Polygon PoS history a query covers, while pagination determines how many matching records appear in each response. The fromBlock and toBlock parameters name the starting and ending blocks. Keeping these bounds fixed makes page continuation easier to reconcile. The offset parameter controls records per page; page selects subsequent records. A response that fills a requested page can leave further matching logs outside that page. Its final row does not establish the end of the matching records within that block range.

Large queries can time out even when their filters are valid. Smaller block ranges reduce the dataset that each request must search. API rate limits remain a separate constraint that depends on the selected plan.

Retain the filter parameters and completed block ranges with exported records, so later imports can identify their actual coverage.

Response Fields Distinguish Empty Searches From Errors

Check the API response’s status , message and result fields to distinguish a valid empty result from an error. A status value of 0 can indicate either an error or a valid search with no records. Invalid credentials, unsupported chain selection and rate limiting require different corrections from a genuine no-match result. A timeout also leaves coverage unresolved. An unsuccessful request cannot establish that a contract emitted no matching events within the requested block range.

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A valid empty result describes that particular filter and block range. It says nothing about events outside those conditions.

Event Decoding Determines the Meaning of a Match

Decoding a matching log gives its raw values the types and field meanings that the event declaration specifies. Contract verification can make that interface available beside published source code. Amount fields require their documented units. For ERC-20 amounts, human-readable scaling uses that token’s decimal precision when the token defines it. Historical token approval events describe recorded changes, while current permissions come from the relevant contract state. A matching signature alone establishes neither a token’s authenticity nor the authority of its emitter.

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