Transposition for Woodwinds

Most woodwinds are transposing instruments: the note the player reads is not the note that comes out. This was originally a practical convenience — back when instruments came in many different keys, transposition let players use the same fingering across the family. We're still living with the historical convention.

The Cheat Sheet

Instrument	Written Range	Sounding	Transposition
Piccolo	d¹–c⁴	Sounds 8va higher than written	Octave
Flute (C)	c¹–c⁴	At pitch	Concert (non-transposing)
Alto Flute (G)	c¹–c⁴ written	Sounds P4 lower	In G
Oboe	bb–a³	At pitch	Concert
English Horn	b–g³ written	Sounds P5 lower	In F
Clarinet in Bb	e–g³ written	Sounds M2 lower	In Bb
Clarinet in A	e–g³ written	Sounds m3 lower	In A
Bass Clarinet	e–g³ written	Sounds M9 lower (treble)	In Bb
Soprano Sax	bb–f³ written	Sounds M2 lower	In Bb
Alto Sax	bb–f³ written	Sounds M6 lower	In Eb
Tenor Sax	bb–f³ written	Sounds M9 lower	In Bb
Baritone Sax	bb–f³ written	Sounds 8va + M6 lower	In Eb
Bassoon	Bb1–eb²	At pitch (bass/tenor clef)	Concert
Contrabassoon	Bb1–bb¹ written	Sounds 8va lower	Octave (bass)

The Mnemonic

A "Bb instrument" written C → sounds Bb.

Whatever pitch you write, the instrument sounds the pitch its name implies. An Eb alto sax written C → sounds Eb. A Bb tenor sax written C → sounds Bb. A horn in F written C → sounds F. The instrument's name is its written-C → sounding-pitch reference.

Why Bb Clarinet and A Clarinet?

Orchestra clarinet players carry both. The choice depends on the key signature: Bb clarinet is more comfortable in flat keys (a piece in F major reads as G major); A clarinet is more comfortable in sharp keys (a piece in E major reads as G major). Same instrument, same fingerings — just a different barrel.

Score vs Parts

Concert-pitch score — fine for sketching and analysis, but not what the player needs.
Transposed parts — what each player actually reads. Sibelius/MuseScore/Dorico will produce these automatically from a concert-pitch score, but you have to ask for them.
C-score for conductor — many conductors prefer concert-pitch full scores so they can hear the harmony at a glance.

A Practical Rule

Don't transpose in your head while composing. Sketch in concert pitch, let the notation software handle the parts. The most common mistake young composers make is hand-transposing as they write, getting an octave wrong, and not noticing until rehearsal.