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Transposition · Brass

What key is the trumpet in?

Quick answer. The trumpet is a B♭ transposing instrument. When a player reads a written C, the pitch that actually sounds — what a piano would play — is concert B♭, a major second lower than written. So trumpet music is written a major second higher than it sounds. In practice: when your band director calls “concert B♭,” the trumpet reads and plays a written C.

What that means on the page

A transposing instrument is one whose written notes do not match the concert pitch that sounds. The trumpet is one of them: it sounds a major second (two semitones) lower than written. Read a written C and the audience hears concert B♭.

That is why it is called a B♭ instrument: a written C produces the pitch B♭, the key the instrument is built around.

Concert pitch to what the trumpet reads

The most useful version of this in a rehearsal is the reverse direction — the director names a concert pitch and you need to know what to read. Add a major second:

When the director says “concert ___,” the trumpet reads and plays:
Concert pitch (sounds)B♭ Trumpet reads
Concert B♭C
Concert E♭F
Concert FG
Concert CD
Concert A♭B♭
Concert GA
Concert DE

The pattern never changes: the trumpet reads a major second above the concert pitch. Internalising this table is one of the fastest ways to feel at home in a concert band or jazz ensemble.

Why the trumpet is written this way

The B♭ trumpet is the standard trumpet of the concert band, the jazz section and the orchestra. Its tubing is built so that the fundamental series starts on B♭, and the music is written so a player reading a C gets that home pitch. The C trumpet used in some orchestras is the same instrument in a shorter length, and it does not transpose at all.

Written range

The standard written range of the trumpet is F♯3 to C6 — sounding a major second lower. That is the range parts are scored in and the range these pages and the app both use.

Why this matters for practice

Because the trumpet transposes, every scale you practise has a written name and a sounding name. The fastest way to build fluency is to practise the twelve major scales in the instrument’s own written pitch, hearing each note as it truly sounds. See the full trumpet fingering chart — every note with its written and concert pitch — or read the method behind mastering all twelve keys.

Frequently asked

What key is the trumpet in?

The trumpet is in the key of B♭. A written C sounds as concert B♭, a major second lower than written.

How much does the trumpet transpose?

It sounds a major second — two semitones — lower than written. To put a concert-pitch melody on the trumpet, write it a major second higher than it sounds.

What does the trumpet play for “concert B♭”?

A written C. Concert B♭ is a major second below written C, so that note sounds concert B♭.

Is the trumpet a transposing instrument?

Yes. Written and sounding pitch are different: the trumpet sounds a major second lower than the note on the page.

What is the written range of the trumpet?

The standard written range is F♯3 to C6. That is what appears on the page; the sounding pitches are a major second lower.

Practice every key in your instrument’s pitch.

The Whole Horn plays all twelve major scales in the trumpet’s written pitch, so you hear concert pitch while you read trumpet.

Get the app → The full transposition chart

By Thomas Hornig — Henri Selmer Paris artist · Professor of Saxophone, Lebanese National Higher Conservatory of Music.
Related: Vibrato Practice — free vibrato trainer · B♭ Trumpet fingering chart · Trumpet scale practice · The full band transposition chart · The method · B♭ Trumpet range