Studio arithmetic: tempo grids, song length, tap tempo, key shifts and capo, Camelot mixing, diatonic chords, fretboard notes, pitch-speed and delay tails.
payments ON MAINNET (real money) · 9 live endpoints
| Endpoint | Price | What it answers |
|---|---|---|
GET /camelot-key | $0.02 | Camelot wheel code for a musical key and its harmonic-mixing matches; optionally test if two keys mix. |
GET /delay-tail | $0.02 | Feedback delay decay: dB lost per repeat, repeats to fall 60 dB and total tail time in ms from delay and feedback. |
GET /diatonic-chords | $0.02 | The 7 triads and 7th chords of a key (major, natural or harmonic minor) with spelled notes and Roman numerals. |
GET /fret-note | $0.02 | Note name, MIDI number and Hz at a fret on guitar, bass, ukulele or violin strings, with alternate tunings. |
GET /key-shift | $0.02 | Shift a key by semitones with the right sharp or flat spelling, its relative major or minor, signature and capo shapes. |
GET /pitch-speed | $0.02 | Convert semitones, cents, speed percent, two frequencies or two BPMs into one varispeed ratio with all equivalents. |
GET /song-length | $0.02 | Song length in seconds and m:ss from bars, BPM and time signature, plus bars or BPM needed for a target length. |
GET /tap-timestamps | $0.02 | Tap tempo from tap timestamps in ms: mean and median BPM, interval spread and jitter percent. |
GET /tempo-grid | $0.02 | Note values 1/1 to 1/32 (straight, dotted, triplet) at a BPM as ms, LFO Hz, samples and MIDI ticks. |
GET /catalog returns this list as JSON. Activity hub · uptime.
Music-production arithmetic computed locally from the numbers you give, using equal temperament with A4 = 440 Hz unless stated. Tempo, key and spelling conventions differ between DAWs, publishers and DJ software: the conventions used are stated in each answer. Not engineering, legal or licensing advice. Every paid response carries a disclaimer field.