#logs

Query any EVM contract's emitted event logs live via the chain's public JSON-RPC, filtered by address, topics and block range, with every log decoded — block, transaction hash, indexed topics and data. A convenience endpoint decodes ERC-20 Transfer events straight into from / to / value. Unlike a single-transaction receipt lookup, this answers "what happened on this contract over this window" — the indexing primitive behind every block explorer, analytics dashboard and on-chain webhook. Pass raw topic hashes or a known event name like Transfer or Approval. Works on any contract, verified or not, across Ethereum, Base, Arbitrum, Optimism, BNB, Polygon and more. Reads straight from the chain; live, short cache only.

api.oanor.com/eventlogs-api

Work with NDJSON / JSON Lines — the one-JSON-value-per-line format used by application and audit logs, streaming and LLM responses, jq, BigQuery, Elasticsearch bulk and many data pipelines. The to-array endpoint parses an NDJSON stream into a regular JSON array; to-ndjson does the reverse, turning a JSON array into NDJSON (one compact value per line); and validate checks every line independently, reporting which lines are valid and the exact parse error for any that are not. Blank lines are ignored. Perfect for log processing, ETL, data import/export and stream debugging. Pure local computation — no key, no third-party service, instant; up to 4 MB via POST. Live, nothing stored. 4 endpoints. Distinct from JSON validation/formatting and from CSV tooling.

api.oanor.com/ndjson-api