Chord Transposer
Transpose a chord or chord progression by any number of semitones.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
Transposing a progression means moving every root by the same number of semitones while keeping its quality, so an Am7 becomes a Bm7 when shifted up two. Writing it out matters because a capo or a new key can otherwise mean relearning the whole song.
Worked example
calculated with the default values below
Chords (space separated) C Am F G · Semitones to transpose 2 · Prefer sharps or flats Sharps Transposed chords D Bm G A · Semitones moved 2 · First chord as entered C · New first chord D · Capo position that gives the same result Capo at fret 2
General background references
Disclaimer
These calculators give general estimates. Sizing, pricing, availability and standards vary by brand, retailer and country, so treat the output as a starting point and confirm it against the seller's or authority's own figures.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
j = (i + s) mod 12; capo = (−s) mod 12
- i
- Original pitch class (0 = C)
- s
- Semitone shift
- j
- New pitch class
- capo
- Capo position (frets)
Wraps at 12 semitones; chord suffixes (m, 7…) are kept; choose sharp or flat spelling.
Frequently asked questions
How do slash chords and capo positions work?
The calculator transposes both the root and bass note in slash chords, so C/E shifted up two semitones becomes D/F#. For a positive shift, the capo result uses that fret number so the original shapes sound in the new key; negative shifts use the equivalent pitch-class fret modulo 12. This is a pitch-class aid, not a complete fingering or arrangement.