Transpose Calculator
Pick a key and how many semitones to move, paste a chord progression, and get the new key and chords. The instrument section converts between concert pitch and B♭, E♭ and F parts.
Positive = up, negative = down
New key
D
2 semitones up, a major 2nd
Separate chords with spaces. Slash bass notes work: C/E, Am7/G
D A Bm G
Transposing instruments
Shift the written part
up 2 semitones
written C becomes D
Every key from C
| Semitones | Interval | New key | Capo (guitar, play in C shapes) | Pitch ratio |
|---|---|---|---|---|
| +0 | unison | C | open | ×1.0000 |
| +1 | minor 2nd | Db | fret 1 | ×1.0595 |
| +2 | major 2nd | D | fret 2 | ×1.1225 |
| +3 | minor 3rd | Eb | fret 3 | ×1.1892 |
| +4 | major 3rd | E | fret 4 | ×1.2599 |
| +5 | perfect 4th | F | fret 5 | ×1.3348 |
| +6 | tritone | F# | fret 6 | ×1.4142 |
| +7 | perfect 5th | G | fret 7 | ×1.4983 |
| +8 | minor 6th | Ab | fret 8 | ×1.5874 |
| +9 | major 6th | A | fret 9 | ×1.6818 |
| +10 | minor 7th | Bb | fret 10 | ×1.7818 |
| +11 | major 7th | B | fret 11 | ×1.8877 |
How transposition works
There are twelve pitches in an octave and they repeat, so a key is a position on a clock face. Transposing by n semitones moves every note n positions around the clock; the intervals between notes, and therefore the chord qualities, are unchanged. Up 7 and down 5 land in the same place, so the calculator shows both the direction you asked for and the enharmonic spelling that suits the new key.
Transposition chart, all twelve keys
| From \ up | +1 | +2 | +3 | +4 | +5 | +6 | +7 | +8 | +9 | +10 | +11 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| C | Db | D | Eb | E | F | F# | G | Ab | A | Bb | B |
| Db | D | Eb | E | F | F# | G | Ab | A | Bb | B | C |
| D | Eb | E | F | F# | G | Ab | A | Bb | B | C | Db |
| Eb | E | F | F# | G | Ab | A | Bb | B | C | Db | D |
| E | F | F# | G | Ab | A | Bb | B | C | Db | D | Eb |
| F | F# | G | Ab | A | Bb | B | C | Db | D | Eb | E |
| F# | G | Ab | A | Bb | B | C | Db | D | Eb | E | F |
| G | Ab | A | Bb | B | C | Db | D | Eb | E | F | F# |
| Ab | A | Bb | B | C | Db | D | Eb | E | F | F# | G |
| A | Bb | B | C | Db | D | Eb | E | F | F# | G | Ab |
| Bb | B | C | Db | D | Eb | E | F | F# | G | Ab | A |
| B | C | Db | D | Eb | E | F | F# | G | Ab | A | Bb |
Read across from the original key. Up 12 returns to the same key an octave higher.
Instrument offsets
B♭ trumpet, clarinet and soprano sax are written two semitones above concert pitch; tenor sax and bass clarinet are B♭ instruments too but sound an octave lower, so their parts are written 14 semitones (a major ninth) above. E♭ alto sax is written nine semitones above (a major sixth); E♭ baritone sax is another octave, 21 semitones. F instruments (French horn, English horn) are written seven semitones, a perfect fifth, above. Bass clarinet and baritone sax add an octave on top. To convert between two transposing instruments, subtract one offset from the other, which is what the instrument section does: a trumpet part rewritten for alto sax moves up seven semitones.
Frequently Asked Questions
How do I transpose a song to a different key?
Count the semitones from the old key to the new one and move every chord root by the same amount, keeping the chord quality. C to D is two semitones up, so C G Am F becomes D A Bm G. The calculator does this for a whole progression, including slash-chord bass notes, and picks sharps or flats to suit the new key.
How does a capo relate to transposing?
A capo at fret n raises everything you play by n semitones while you keep the same chord shapes. To play a song in E using G shapes, that is 9 semitones up (or 3 down, since keys wrap around every 12), so capo 9, or more practically, choose shapes a few frets lower. The table lists the capo fret for every key from your starting key.
What is a transposing instrument?
One whose written notes sound at a different pitch. A B♭ trumpet playing a written C sounds a B♭, two semitones lower; a tenor sax playing a written C sounds the B♭ an octave below that, 14 semitones lower. An E♭ alto sax playing a written C sounds an E♭, nine semitones lower; a baritone sax sounds the E♭ an octave below that, 21 lower. To write a part from concert pitch, transpose up by that amount: a concert C part is written as D for trumpet and as A for alto sax. The instrument section above does the offset for you.
Why does the same note sometimes show as a sharp and sometimes as a flat?
They are the same pitch spelled two ways (enharmonics). Key signatures with flats (F, B♭, E♭, A♭, D♭) spell their notes with flats, and sharp keys (G, D, A, E, B, F♯) with sharps, so the chords read naturally on the page. The calculator follows that convention automatically.
How much should I transpose for a singer?
Find the highest note in the song and the highest note the singer can hit comfortably, and move by the difference. Most songs move one to three semitones; more than five and guitar shapes get awkward and a capo or different voicings help. Many pop songs are recorded in keys chosen for guitar or piano convenience rather than for the vocalist, so transposing is normal.
These tools use the standard tempo, pitch and timing formulas (60,000 ÷ BPM, A4 = 440 Hz equal temperament, 1,200 cents per octave). They run in your browser; the tap counter uses your keyboard or mouse timing, so expect a beat or two of settling before the reading is stable.