One control serves intervals and note transposition
As a musical interval calculator, the signed semitone field measures pitch distance and prints cents plus a frequency ratio. To transpose notes online, enter the starting register and move upward or downward; the destination keeps its octave visible so crossing a C boundary is never hidden.
See enharmonic spelling and octave movement separately
The result keeps one practical display spelling while the semitone count remains pitch-class math. Crossing B to C or C to B changes the octave at the exact boundary instead of leaving the register implicit.
The ratio is the audit line
Every semitone multiplies frequency by the twelfth root of two. The page prints the accumulated ratio, so the interval can be checked without trusting only the note label.
Negative movement works without a second calculator
Enter a negative distance for downward transposition. Cents retain the sign, while the destination note and octave show where the pitch lands.
Questions
These answers distinguish note names, pitch distance, and register.
Is a semitone always one hundred cents?
In twelve-tone equal temperament, yes; the result uses that definition.
Why can two names describe one key?
Enharmonic names such as C-sharp and D-flat can refer to the same equal-tempered pitch while serving different notation contexts.
Does the calculator hear audio?
No. It performs deterministic note and interval math.
Sources behind the method
The tool combines published music-theory definitions with formulas exposed directly in its result.
Calculations and microphone analysis run locally in this browser.