Music Theory Calculators
BPM, key transposition, intervals, chords, scales, tempo and tuning calculators for musicians.
BPM Calculator
Tap to detect BPM or convert between beats per minute and milliseconds per beat. Free online tempo detection tool for musicians and DJs.
Key Transposition Calculator
Transpose chords and notes between any musical keys instantly. Free online key transposition calculator for musicians and producers.
Interval Calculator
Find the musical interval between any two notes with semitone count, frequency ratio and cents. Free interval calculator for musicians.
Chord Calculator
Build chords from any root note and view the notes, intervals and frequency ratios. Free online chord building calculator for musicians.
Scale Calculator
Generate musical scales from any root note including major, minor, pentatonic, blues and modal scales. Free online scale calculator.
Tempo Calculator
Convert BPM to note durations in milliseconds for setting delay, reverb, LFO and other tempo-synced effects. Free online calculator.
Time Signature Calculator
Calculate bar lengths, beat durations and total song duration from any time signature and BPM. Free online music timing calculator.
Metronome Calculator
Calculate beats per bar, subdivision timings and practice tempo progressions for systematic musical practice. Free online calculator.
Note Frequency Calculator
Find the exact frequency in Hz of any musical note in any octave using equal temperament tuning. Free online note frequency calculator.
Tuning Calculator
Calculate note frequencies for equal temperament, just intonation and Pythagorean tuning systems with adjustable A4 reference pitch.
10 free calculators in Music Theory
Music Theory Fundamentals
Music theory provides the framework for understanding how music works. From the relationship between notes and intervals to the construction of scales and chords, these calculators help musicians, producers and students work through the mathematical side of music quickly and accurately.
In equal temperament tuning (the standard for most Western music), each semitone is separated by a frequency ratio of the twelfth root of 2 (approximately 1.05946). This means A4 at 440 Hz gives A5 at 880 Hz — exactly double. Our note frequency calculator uses this formula to find the precise frequency of any note in any octave.
BPM (beats per minute) is the standard measure of tempo. Knowing the exact BPM of a track is essential for sync, delay timing, and production work. Our BPM calculator lets you tap to detect tempo or convert between BPM and millisecond values for delay effects.