The clarinet is a relative latecomer among orchestral woodwinds, emerging only in the early 18th century—centuries after the flute and oboe's ancestors. It descended from the chalumeau, a simple single-reed folk instrument popular in Europe with a soft, limited range confined mostly to its lowest register.

Around 1700, German instrument maker Johann Christoph Denner, working in Nuremberg, is credited with transforming the chalumeau into the clarinet. Denner added a register key and reshaped the bore and mouthpiece, allowing the instrument to overblow at the twelfth (rather than the octave, as most woodwinds do), unlocking a bright, trumpet-like upper register that gave the instrument its name—from the Italian "clarino," referencing that clarion-like sound.

Early clarinets had only two or three keys and were temperamental, but composers quickly took interest. By the mid-18th century, makers had expanded the keywork, improving intonation and chromatic playability. Mozart became one of the instrument's great champions, writing his Clarinet Concerto and Quintet for the virtuoso Anton Stadler, whose specially extended "basset clarinet" reached lower pitches than standard instruments of the time.

The 19th century brought the clarinet's most transformative redesign. In the 1840s, French clarinetist Hyacinthe Klosé and instrument maker Louis-Auguste Buffet adapted the Boehm system—originally developed for the flute—to the clarinet. This system of rings and rollers dramatically improved fingering logic, intonation, and technical fluency, and remains the dominant design used internationally today, known as the Boehm clarinet.

A separate German/Austrian tradition, the Oehler system, developed in parallel and persists in German orchestras, valued for its distinctive tonal warmth.

Through the 19th and 20th centuries, the clarinet became indispensable across classical, military band, klezmer, and jazz traditions—prized for its extraordinary dynamic range and chameleon-like tone, from woody chalumeau depths to piercing clarion heights.