What Is Alto Clef?

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You might know treble and bass clefs, but what about alto? Some instruments produce a sound and have musical notes that do not fall within the tenor, treble, or bass clefs. The alto clef has notes that fall within the alto range. Here is a closer look at this seldom-used clef.

What Is the Alto Clef?

Picture showing the alto clef symbol

A music staff has five lines and four spaces. When musicians look at a sheet of music, they locate the middle C note because it helps them find other notes on the music staff with the instrument they are playing. Musicians do this regardless of the clef they are in, whether clef is alto, treble, bass, or tenor.

Some people also call it as C clef or viola clef because it falls in the middle of the staff or the C note. Unlike the bass clef, alto’s lines are different. From top to bottom, the lines will be F, A, C, E, G. The spaces, on the other hand, are G, B, D, F.

Why Does Alto Clef Exist?

This clef exists because there are musical instruments that do not fit in the treble, bass, or tenor clefs – alto notes are too high for the bass clef staff and too low for the treble clef staff. Having an alto clef solves this problem by placing most of the alto notes on a musical staff for easier reading.

What Instrument Reads Alto Clef?

Several instruments use this clef. As mentioned, the alto clef is sometimes known as the viola clef since the viola is the primary instrument that uses the alto clef. This is because one of the instruments that read the alto clef is the viola. The range of notes on the viola perfectly corresponds with the note in this clef. Other instruments that use this clef include:

  • Alto trombone
  • Viola de gamba
  • Mandola

The cello also uses some notes in this clef when the melodies are in the higher register.

How Do You Identify It?

A clef is one of the first symbols you will see on a music sheet. The clef for alto instruments starts with a thick vertical line followed by a thin vertical line. Then there is a symbol that looks like an unusual-looking number 3. This symbol fits within the five lines of the staff. This clef is not as well-known as the treble or bass clef because very few instruments use the alto range of notes.

Alto vs. Tenor: What Is the Difference Between Alto and Tenor Clefs?

Picture showing the difference of alto and tenor clefs

The alto and tenor clefs use the same symbol, but there are two differences. The first difference is the placement of the tenor clef. The tenor clef is one line above the alto symbol, so it does not fit within the five lines of the music staff. The second difference is the location of the tenor middle C. Middle C in the tenor clef is also one line above the alto middle C.


Learning the alto range of notes can help to improve your musicianship, compositions, and music study. There is a lot of music written in the alto range that you can access to expand your repertoire. Studying alto clef notes can help you to have a better understanding of music theory and orchestration.


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