Chord Transposer
Free online chord transposer for musicians — select any root note and chord type, then transpose by semitones up or down. Supports Major, Minor, 7th, and more chord types.
About This Calculator
The Chord Transposer Calculator helps musicians, songwriters, and music students transpose any chord to a different key or by a specific interval. Whether you are arranging a song for a different vocal range, adapting sheet music for a transposing instrument like the alto saxophone or clarinet, or simply exploring how a chord progression sounds in a new key, this tool gives you instant results with a clear note-by-note breakdown.
The calculator uses standard music theory: each note in the chromatic scale is assigned a pitch class from 0 to 11 (C=0, C#=1, ..., B=11). A chord is defined by its intervals from the root. For example, a major chord has intervals 0, 4, and 7 semitones (root, major third, perfect fifth). To transpose, the root is shifted by the specified number of semitones in the chosen direction, and the chord is rebuilt using the same interval structure. The formula is: transposedRoot = (originalRoot ± semitones) mod 12.
The calculator supports 13 chord types including Major, Minor, Augmented, Diminished, Sus2, Sus4, Dominant 7th, Major 7th, Minor 7th, Diminished 7th, Half-diminished 7th, Major 6th, and Minor 6th. These cover virtually all chords used in Western music from classical to jazz to contemporary pop. The transposition range is 0 to 12 semitones (one octave), which covers all practical transposition needs including common intervals like the perfect fourth (5 semitones), perfect fifth (7 semitones), and octave (12 semitones).
Each result shows both the original and transposed chord names with their constituent notes, a comparison chart displaying the pitch class mapping, and a breakdown table that maps every original note to its transposed counterpart. The URL saves your inputs automatically, making it easy to share specific transpositions with bandmates or students.
Frequently Asked Questions
How does the chord transposer work?
The chord transposer moves each note in a chord by the same number of semitones to produce a new chord. Select the root note and chord type, enter the number of semitones, choose up or down direction, and the calculator shows the original notes, the transposed root, and the new chord notes. For example, C major (C-E-G) transposed up 4 semitones becomes E major (E-G#-B).
What chord types does the calculator support?
The calculator supports 13 chord types: Major, Minor, Augmented, Diminished, Suspended 2nd (Sus2), Suspended 4th (Sus4), Dominant 7th, Major 7th, Minor 7th, Diminished 7th, Half-diminished 7th (min7b5), Major 6th, and Minor 6th. These cover the most commonly used chords in pop, rock, jazz, classical, and contemporary music.
What is a semitone in music?
A semitone (or half step) is the smallest musical interval in Western music, equivalent to the distance between two adjacent keys on a piano. For example, C to C# is one semitone up, and E to D# is one semitone down. Transposing by 12 semitones moves the chord up or down exactly one octave.
How do I transpose a chord from one key to another?
To transpose a chord between keys, count the number of semitones between the two key roots. For example, C major to G major is 7 semitones up. If you have a D minor chord (D-F-A) in the key of C and want it in the key of G, transpose D up 7 semitones to A — the chord becomes A minor (A-C-E), preserving the chord quality.
What is the difference between transposing by interval and by key?
Transposing by interval moves the chord by a fixed number of semitones regardless of key, which is useful when adapting music for vocal ranges or instruments. Transposing by key moves the chord from one key to another by the semitone distance between the two key roots, which preserves the harmonic relationship of the chord within the new key.
Why are sharps and flats used in transposed chords?
Sharps (#) and flats (b) indicate whether a note is raised or lowered by a semitone. The calculator uses sharp notation consistently. For example, C# and Db are the same pitch but written differently depending on the musical context. The correct enharmonic spelling depends on the key signature, but for most practical purposes the pitch is the same.
Can I use this calculator for writing music?
Yes, the chord transposer is ideal for songwriting, arranging, and composition. Use it to quickly find how a chord progression sounds in a different key, adapt music for instruments with different ranges (like transposing for alto sax or clarinet), or experiment with reharmonization by moving chords up or down by specific intervals.
Does the chord quality change when transposing?
No, the chord quality stays the same when transposing. A major chord remains major, a minor 7th stays minor 7th, and so on. This is because all notes in the chord move by the same number of semitones, preserving the interval structure between them. Only the root and the individual note names change.