Transpose a note

music.openverbs.com · 5 paid endpoints · listed 2026-10-27

Parse a note in scientific pitch notation (e.g. "A4", "C#5", "Bb3") into its letter, accidental, pitch class (0..11), octave, MIDI number and frequency in Hz (A4 = 440 Hz).

livelast check 5 days ago

100%valid x402 answers, 72 h

sharedUSDC received on Base, 7 days

28distinct payers, 7 days

69.9score (0-100)

Paid endpoints

Method	Endpoint	Price	Networks
POST	music.openverbs.com/v1/chord Build a chord from a root note and quality (major, minor, dim, aug, maj7, min7, dom7, dim7, half-dim7, sus2, sus4, maj6, min6). Notes are spelled by stacked thi	$0.002	Base
POST	music.openverbs.com/v1/interval Name the interval between two notes (`to` at or above `from`) — its size in semitones, its diatonic number and its quality (perfect/major/minor/augmented/dimini	$0.002	Base
POST	music.openverbs.com/v1/note Parse a note in scientific pitch notation (e.g. "A4", "C#5", "Bb3") into its letter, accidental, pitch class (0..11), octave, MIDI number and frequency in Hz (A	$0.002	Base
POST	music.openverbs.com/v1/scale Build a scale from a root note and type (major, natural-minor, harmonic-minor, melodic-minor, dorian, phrygian, lydian, mixolydian, locrian, major-pentatonic, m	$0.002	Base
POST	music.openverbs.com/v1/transpose Transpose a note by a (possibly negative) number of semitones. Result is spelled chromatically with sharps, or flats when `preferFlats` is true.	$0.002	Base

Latest checks

When	Endpoint	HTTP	ms	Result
5 days ago	music.openverbs.com/v1/chord	402	579	valid x402 v2 terms

Income on Base (7 days)

This provider's payout address is shared by several providers, so its income is not shown as its own.

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Income is all USDC received by the provider's payout address on Base, whatever the source. Score: 0-100: 50 x share of checks in the last 72 h that returned valid x402 payment terms + 30 x min(1, log10(1 + USDC received in 7 days) / 4) + 20 x min(1, log10(1 + distinct payers in 7 days) / 3). A provider never checked scores on income only; income is all USDC received by its payout address on Base, whatever the source. JSON: /v1/observatory/providers/music.openverbs.com