{"slug":"music-theory-x402tookit-com-freq-note-9450cd","title":"Frequency in Hz to the nearest note, MIDI number and offset in cents; adjustable","host":"music-theory.x402tookit.com","method":"GET","resource":"https://music-theory.x402tookit.com/freq-note","category":"other","description":"Frequency in Hz to the nearest note, MIDI number and offset in cents; adjustable A4 reference; tuner-style result.","price_listed":0.02,"price_asked":0.02,"state":"answering","state_label":"Answering","checks_7d":1,"answered_7d":1,"latency_ms_median":1398,"reported_calls_30d":1,"reported_payers_30d":1,"networks":["eip155:137","eip155:42161","eip155:8453","solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"method":"GET","queryParams":{"hz":442},"type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"method":{"enum":["GET"],"type":"string"},"queryParams":{"properties":{"a4":{"description":"Reference pitch for A4 in Hz, 400 to 480 (default 440)","type":"number"},"accidentals":{"description":"sharps (default) or flats for the note name","type":"string"},"hz":{"description":"Frequency in Hz, 8 to 14000","type":"number"}},"required":["hz"],"type":"object"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"},"output":{"properties":{"example":{"properties":{"a4Hz":{"type":["null","number"]},"asOf":{"type":["null","string"]},"centsOffset":{"type":["null","number"]},"degraded":{"type":["boolean","null"]},"direction":{"type":["null","string"]},"disclaimer":{"type":["null","string"]},"fractionalMidi":{"type":["null","number"]},"frequencyHz":{"type":["null","number"]},"midi":{"type":["null","number"]},"nearestFrequencyHz":{"type":["null","number"]},"nearestNote":{"type":["null","string"]},"notChecked":{"items":{"type":"string"},"type":["array","null"]},"reasons":{"items":{"type":"string"},"type":["array","null"]},"source":{"type":["null","string"]},"summary":{"type":["null","string"]},"verdict":{"type":["null","string"]}},"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[{"day":"2026-10-21","reachable":true,"status":402,"valid_402":true,"asked_usdc":0.02,"price_match":true,"latency_ms":1398,"error":null}],"description_full":"Frequency in Hz to the nearest note, MIDI number and offset in cents; adjustable A4 reference; tuner-style result.","last_updated":"2026-10-20T20:46:45.813Z","schemes":["exact"]}