How to Transpose Any Song in a Matter of Minutes

Changing the key signature of a song used to be difficult for me. That was until my dad taught me to transpose using a system that made it so simple.

At the time, we didn’t really know the official name for it, so we just said that we were learning to “play by number.” I now know that it’s called the Nashville Numbering System (NNS).

The NNS is a system that numbers the chords in a way that they can be used in any key. The best way to explain it is by showing you how it works. Let’s use the Christmas carol, O Come All Ye Faithful, since it’s a popular song to many.

1. Identify the chord numbers.

Place a number next to each chord. This little chart comes in handy for this. The numbers stand for which scale degree each chord finds it root.

Example 1

Verse
G (1) D (5)
O come, all ye faithful
G (1) D (5)
Joyful and triumphant
Em (6m) D (5) A (2) D (5)
O come ye, o come ye to Bethlehem
G (1)
Come and behold Him
Am (2m) D (5)
Born the King of Angels!

Chorus
G (1)
O come, let us adore Him
G (1) D (5)
O come, let us adore Him
C (4) D (5)
O come, let us adore Him
G (1) D (5) G (1)
Christ the Lord

2. Find any borrowed chords.

Notice that there is one chord that doesn’t fit in the NNS. It’s the A chord (highlighted), which is a borrowed chord from the key of D. It is the 5 chord in D and technically speaking it is the 5 of 5 in the key of G.

Example 2

Verse
G (1) D (5)
O come, all ye faithful
G (1) D (5)
Joyful and triumphant
Em (6m) D (5) A (2) D (5)
O come ye, o come ye to Bethlehem

3. Transpose the chords to a new key.

Let’s transpose it to the key of E. The E scale is as follows: E (1), F# (2), G# (3), A (4), B (5), C# (6), D# (7). Use the chord numbers in the song to determine which degree of the scale correlates with each chord.

Example 3

Verse
(1) (5)
O come, all ye faithful
(1) (5)
Joyful and triumphant
(6m) (5) (2) (5)
O come ye, o come ye to Bethlehem
(1)
Come and behold Him
(2m) (5)
Born the King of Angels!

Chorus
(1)
O come, let us adore Him
(1) (5)
O come, let us adore Him
(4) (5)
O come, let us adore Him
(1) (5) (1)
Christ the Lord

Example 4

Verse
E (1) B(5)
O come, all ye faithful
E (1) B (5)
Joyful and triumphant
C#m (6m) B( 5) F# (2) B (5)
O come ye, o come ye to Bethlehem
E (1)
Come and behold Him
F#m (2m) B (5)
Born the King of Angels!