Log Filter Query Builder

WHAT IT DOES

Log Filter Query Builder is a developer-focused utility that constructs and executes eth_getLogs queries to inspect historical event logs on EVM chains. It reads the current chain state and block number for context, accepts user-defined filter parameters including contract address, block range (from and to block), and up to four topic filters (topic0 through topic3) for indexed event parameters. The tool executes the query via eth_getLogs and displays the results in a structured format, showing each log's address, transaction hash, block number, topics, data payload, and log index. It provides immediate feedback on the number of logs found and displays a summary of the applied filter. This enables developers and auditors to efficiently search for specific events emitted by contracts without writing manual RPC requests.

HOW TO USE

Connect your wallet to the target EVM chain. Optionally enter a contract address to filter logs by a specific contract. Specify a block range by entering from and to block numbers (e.g., "12345678" and "12345679") or use the default "latest" for the most recent blocks. Enter up to four topic filters as hex strings (e.g., event signature hashes or indexed parameter values) to narrow down the search. Click "Query logs" to execute the eth_getLogs request. The tool will display the total number of logs found, the current block number, a summary of the applied filter, and a detailed list of each log entry. Each log entry shows the contract address (with a link to the explorer), transaction hash (with link), block number, log index, all topics, and the data payload if present.

TECHNICAL NOTE: CHUNKED LOG QUERY WITH AUTOMATIC BACKOFF

The tool implements a robust log query strategy that automatically handles RPC provider limitations. For block ranges that exceed provider caps (commonly 10,000 blocks on many public RPCs), the tool chunks the range into smaller segments and executes sequential queries, halving the chunk size on each refusal or timeout. This ensures log scans complete even on public RPCs with aggressive caps. The tool also validates all inputs: contract addresses are checked for checksum validity, block numbers are parsed as integers, and topic filters are validated as hex strings. After executing the query, the tool displays the logs with transaction and address links to the block explorer for the selected chain.

WHAT IT CANNOT SEE

The tool cannot query logs beyond the RPC provider's archival limits, meaning very old blocks may not be available if the provider does not support archival data. It cannot decode logs without the correct contract ABI; the tool displays raw topics and data but does not parse named event parameters. It cannot filter by non-indexed parameters efficiently, as these are not indexed in the log and cannot be filtered at the RPC level. It cannot query logs across multiple chains simultaneously; queries are limited to the currently selected network. The tool is limited by eth_getLogs block range restrictions; some providers cap at 10,000 blocks per request. It cannot detect events that were not emitted as logs, such as internal transactions or function calls that do not emit events. It cannot query pending logs from the mempool, as eth_getLogs only returns confirmed logs.

PLEASE NOTE

This tool is designed exclusively for EVM-compatible chains (Ethereum, Polygon, BSC, Arbitrum, Optimism, Avalanche C-Chain, etc.). It does not support non-EVM blockchains. The tool uses the connected wallet's RPC provider; results depend on the provider's archival capabilities and rate limits. For large block ranges, the tool may take time to complete. Topics are expected as hex strings (0x-prefixed). The tool is read-only and does not modify any state. The tool provides no warranty of data completeness; users are responsible for verifying log data from multiple sources when performing forensic analysis.