How To Transpose Up A perfect 4th: A Music Theory Guide

By Jade Bultitude
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Transposition is essential skill for any aspiring musician. At their heart of it, transposition allows you to alter music so that it can be played on different instruments or in different ranges of pitch.

So let’s take a dive into how to transpose up a perfect 4th. This is both for music theory students and for musicians seeking to understand the concept of transposition.

Need to transpose using another interval; check out all our transposition guides here.

What Is A Perfect 4th?

A perfect 4th interval is created when we move from the 1st degree of the scale to the 4th degree to the scale. This interval is called a ‘perfect’ third because it is the 3rd note of the major scale. 

Another way of thinking about a perfect 4th is that it is 5 half-steps above the lower note. More perfect 4th examples here.

perfect 4th C and F

It’s worth remembering that 2nd, 3rd, 6th and 7th intervals can also be major or minor, whereas 4th and 5th intervals are described as ‘perfect’.

Why transpose up a Perfect 4th?

One of the most common uses of this type of transposition is moving from the tenor saxophone to the alto saxophone.

The alto is in Bb and the tenor is in Eb, so to rewrite music from the tenor to the alto we can transpose up a perfect 4th. This will mean that we can play an alto saxophone piece on our tenor saxophone.

In the same way we could transpose a alto piece for the tenor sax. This would involve transposing the piece down a perfect 4th.

alto and tenor saxophone transposition

How To Transpose Up A Perfect 4th

This method has three steps:

  1. Transpose the key signature up a perfect 4th
  2. Move all the notes up a 4th
  3. Deal with the accidentals

(If you thought we could transpose each note one at a time, click here to see why NOT to do this)

Let’s try an example. Have a look at the melody below and let’s transpose it up a perfect 4th.

c major melody

Step 1- Transpose The Key Signature

First, let’s transpose the key signature. Our melody is the key of C major, so what is a perfect 4th above C natural?

c major perfect 4th

As you can see above, a perfect 4th above C is F natural. This means that we now need to put the key signature of F major at the start of our melody. 

The key signature of F major has one flat – Bb.

D natural minor key signature, treble clef

Here it is in our melody.

F major melody with key signature highlighted
  • If you are unclear on your key signatures, please make sure you are familiar with your Circle of Fifths

Step 2- Move The Notes Up A 4th

Once you have changed your key signature, we then need to follow this with moving all the notes in the melody up a 4th. As with all intervals we include the starting note, so effectively this means moving the notes up three times.

f major melody with notes moved up

And we have our transposed melody! Below is the original melody with the tranposition underneath.

There are no accidentals in this melody so no need for step 3 this time.

Example 2

What key is our melody in below?

B flat major melody

That’s correct, we are in B flat Major!

Step 1- Transpose The Key Signature

First let’s transpose the key signature. Can you transpose up a perfect 4th from Bb?

b flat up a perfect 4th transposition

The 4th note of the B flat major scale is E flat. This means we now need the key signature of E flat major. Eb major has three flats – Bb, Eb and Ab.

C natural minor scale key signature

Here is the new key signature at the start of our melody. 

E flat major melody

Step 2- Move The Notes Up A 4th

Now we have changed the key signature, simply move all of your notes up a 4th. 

e flat major melody moved notes up

As you can see, we have not moved the F sharp note yet. This is because it is not in the notes of the original key signature and so will need to be treated differently.

Step 3- Accidentals

In our original melody we have a F#. This note is not in the key of Bb major and so it will not be transposed correctly by the first 2 steps.

To transpose this note we treat it on its own. We can ask: what is a perfect 4th above F#? F# major actually has 6 sharps in it (F#, C#, G#, D#, A# and E#). The 4th note of this scale is B natural. Here is the final transposition alongside the original melody.

transposition up a perfect 4th Bb to Eb

Suppose we didn’t know that F# major had six sharps, is there another way to make transposing this note easier?

The easiest method in this case would be to lower the F# a half-step to an F. Finding a Perfect 4th above F is much easier: it is B flat. Then we raise the Bb up a half-step to correct it to B natural.

f to Bb and F# to B natural perfect 4th examples

Can We Transpose One Note At A Time?

This is the slowest method of transposing, but it works! Here we are going to move each note up a perfect 4th interval to create our transposed melody.

transpose up perfect 4th note by note

Remember that for each different note we need to count up a 4th in a different key. Because of this it can be way easier to make mistakes. You will also need to look at your notes to figure out the key signature for your new melody, otherwise you may have a lot of accidentals to read!

What’s Next….?


How Can I Transpose Sheet Music Up A Perfect 4th Automatically?

There are a variety of apps that can transpose sheet music such as Sibelius and Musescore.

What About Transposing A Piece In A Minor Key Up A Perfect 4th?

If you have a piece in a minor key then transposition works much the same. Remember that a minor piece will be transposed into another minor key even through we are moving it up a perfect 4th. (Similarly a piece with a major key signature will be transposed to another major key).

For example, a piece in A natural minor would be transposed into the key of D minor (one flat – Bb). This is because D natural is the 4th note of the A major scale and the A Minor scale. 

In a way, it’s easier to think of the original key signature without the major/minor label. If the piece is in A minor, just start with the note A natural and transpose from there. Just remember pieces do NOT change whether they are major or minor by transposing them. 

Important- beware of accidentals as these need to be treated independently. Scales such as the harmonic minor and melodic minor use additional accidental outside the key signature.


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Jade is a flute player and music educator with a passion for educating the next generation of musicians. She is a Masters Graduate from Trinity Laban Conservatoire of Music and Dance. Jade has been helping people learn music theory for more than 10 years from pre school children all the way to degree level studies.