Online Clarinet Tuner

One reed, one bore shape, and a register that jumps by a twelfth

A clarinet is a transposing, single-reed instrument with a cylindrical bore — and both of those facts, not just one, decide how it behaves against a tuner. The transposition means what you read is never what you hear: a standard soprano clarinet is pitched in B♭, so written C sounds concert B♭, a whole step lower. The bore shape decides something most players never think about until it bites them: because a cylindrical tube closed at the reed end behaves acoustically like a stopped pipe, it only supports oddharmonics. Press the register key and the note doesn’t jump an octave, the way it does on a flute, oboe or saxophone — it jumps a twelfth (an octave plus a fifth). That single fact is why the clarinet has a chalumeau register and a clarion register with a break between them, rather than one register that simply repeats an octave higher.

This tuner always reports the concert pitch actually in the air, in whichever octave it actually sounds — never the written name on your part. Use the reference tones below in concert pitch, and do the transposition in your head, the way you already do when you read music.

Where the pitch actually comes from

The barrel jointis the clarinet’s one true tuning slide — the short section between the mouthpiece and the upper joint. Pulling it out lengthens the effective tube and flattens the whole instrument; pushing it in shortens and sharpens. It doesn’t act evenly, though: because the barrel sits at the very top of the tube, pulling it changes the upper (clarion and altissimo) register more than it changes the lower chalumeau register. A second gap, at the middle joint where the upper and lower sections meet, is the finer, more even correction — used when the barrel alone has fixed the overall pitch but left the two registers disagreeing with each other.

The reed, mouthpiece and embouchure do the rest, note by note. A softer reed, a more open mouthpiece facing, or simply biting down all sharpen a note; a looser jaw and slower air flatten it. Clarinetists also lean on voicing— raising or lowering the back of the tongue inside the mouth, roughly the shape of an “ee” versus an “aw” vowel, without changing lip pressure at all — to bend a note tens of cents in either direction. It is a genuinely different tool from a flutist’s air angle or a trombonist’s slide: nothing on the outside of the instrument moves.

Tuning routine, step by step

1. Warm the instrument through first. A cold clarinet plays flat — pitch follows the temperature of the air column, not the grenadilla or plastic around it — so play for several minutes before trusting any reading.
2. Play the long C at a normal mezzo-forte — written C5, the standard tuning note, sounding concert B♭4. Correct any offset with the barrel joint: sharp, pull out; flat, push in, a millimetre or two at a time.
3. Cross the break and check it again. Play the chalumeau low E (written E3), then the same fingering with the register key added (written B4, a twelfth up). If the low note now reads flat relative to a centred long C, or the twelfth reads sharp, the registers are disagreeing — try the middle joint rather than pulling the barrel further.
4. Check the throat tones on their own. Written G4 through B♭4 sit on small, high tone holes that make them thin and frequently flat regardless of barrel position; most players correct them with an alternate right-hand fingering rather than air alone — see the callout below.
5. Finish by playing, not holding notes. A long tone tells you where the instrument sits at rest; a scale or a phrase tells you where your own voicing habitually pulls it, which is the correction that actually matters in performance.

The clarinet family: switching instrument, not retuning one

Where a guitarist reaches for a capo, an orchestral clarinetist often reaches for a different instrument entirely. The A clarinet, identical in every way except its length, sounds a minor third below written rather than a major second — many Mozart, Brahms and Schumann parts are written for it specifically because it lands the piece's key signature in easier fingerings than the B♭ horn would. Switching means picking up a second, separately calibrated instrument with its own barrel setting, not transposing on the fly.

Below the soprano, the B♭ bass clarinet plays an octave and a step (a major ninth) below what's written, in a wider bore that changes its tone but not the acoustic principle — it still overblows a twelfth. Above it, the small E♭ (piccolo) clarinet sounds a minor third higher than written, used for piercing, cutting-through-the-band parts. An E♭ alto clarinet, pitched between soprano and bass, sounds a major sixth below written. All of them are tuned exactly the way this page describes — barrel first, then registers, then reed and voicing — just at a different transposition and a different physical size.

Equal temperament vs. what a good ear actually does

Like a flute or a trombone, a clarinet has essentially no fixed pitch of its own — voicing and embouchure bend every note far enough that "in tune" against this equal-tempered dial and "in tune" against the chord you're actually playing in are two different targets. A major third locked to the ensemble sits roughly 14 cents below where this tuner calls it centred; a perfect fifth sits about 2 cents above. Chasing a perfectly centred needle on a sustained chord tone fights the ensemble rather than blending with it.

The practical split: use this tuner to calibrate the barrel and to map your own throat-tone and altissimo tendencies, where a fixed, objective grid is exactly the right tool. Use your ears once you're playing inside a chord, where the correct target moves depending on which note of the harmony you're holding. Our guide to cents covers why those two answers disagree by a predictable amount and are both correct.

Frequently asked questions