{"uid":"cap_QYli3DENiN1wZEwGH0T5q","slug":"music-production-calc-fret-note-lookup-c652f4c8","name":"Music Production Calc: Fret Note Lookup","description":"Note name, MIDI number and Hz at a fret on guitar, bass, ukulele or violin strings, with alternate tunings.","url":"https://music-production-calc.x402tookit.com/fret-note?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["instrument","string","fret"],"properties":{"a4":{"type":"number","description":"Reference pitch for A4 in Hz, 400 to 480 (default 440)"},"fret":{"type":"integer","description":"Fret 0 (open) to 24"},"string":{"type":"integer","description":"String number, 1 = highest-pitched in normal numbering (guitar 6 = low E)"},"instrument":{"type":"string","description":"guitar, bass, ukulele or violin"},"tuningOffset":{"type":"integer","description":"Tune the whole instrument by semitones, -12 to 12 (-2 = whole step down); 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It is ideal for music production tools, fretboard educators, MIDI mapping assistants, and tuning analysis workflows where instrument-specific string/fret lookup is required rather than general music theory computation.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-29T13:08:24.822Z","isFirstParty":false,"canonicalSlug":"music-production-calc-fret-note-lookup-c652f4c8"}