French Horn Tuner Online — Free F Horn

The french horn is a brass instrument whose tubing is built in F by default, and the F horn sounds a perfect fifth below written pitch. This free online french horn tuner uses your microphone in the browser — no app or sign-up. The right hand inside the bell is a continuous pitch control, and it has to be in place before any reading is meaningful.

How to use it

1. Start the tuner. Press Start Tuner (Microphone) and allow microphone access. The audio is analysed in your browser; nothing is uploaded.
2. Put your right hand in the bell first. Set the hand in its normal playing position before you play a note, because the hand changes the pitch the tuner hears.
3. Warm up before tuning. Cold brass is flat, and the horn’s pitch also settles as the hand position and air become consistent.
4. Read the display a perfect fifth below your part. A written C shows as F, a written G shows as C. Convert before deciding the reading is wrong.
5. Work with the slide and the hand together. The tuning slides set the instrument; the right hand adjusts pitch continuously as you play.
6. Tune the double horn in the recommended order. B♭ side first on a written C, then the F side on a written C or G, with the hand in the bell throughout.
7. Check the octaves and the hand position. An F that reads correctly with the hand out of position will not read correctly once you play — verify in playing position.
8. Re-check after a few minutes. The horn is metal and warms quickly relative to its size; the reading will rise as it does.

Written pitch and sounding pitch

• The horn in F sounds a perfect fifth below written. Wikipedia states it directly: “In F the horn sounds a perfect fifth lower than written.” Written middle C therefore sounds the F below it.
• The double horn is the usual instrument. Wikipedia notes that the double horn in F/B♭ “is the horn most often used by players in professional orchestras and bands”. It combines an F side and a B♭ side, but the written notation does not change: most notes can be played on either side.
• Horn notation already sits in a high part of the harmonic series. Wikipedia’s article on the pitch of brass instruments notes that “what is written as middle C for the horn is the fourth harmonic of the unlengthened instrument, not the second”, and that horn music uses a higher range of the series than most modern brass — part of why the instrument feels different from the trumpet and trombone.
• The B♭ rotor is not a transposition you read. Brass pedagogy explains that pressing the B♭ rotor transposes the instrument up a perfect fourth while the written notation stays the same. The player changes fingerings, not reading.

How to read this tuner as a french horn player

Written note	Sounds as	The display shows
C4 (written middle C)	F3	F3
G4	C4	C4
C5	F4	F4
Written C4 with the band on concert F	F3	F3

Which note to tune to

• Concert F is the standard band tuning note. Yamaha’s intonation guide calls concert F and concert B♭ solid choices for bands. On the F side of the horn, a written C sounds concert F — so the horn’s written tuning note is a C.
• The double horn has an order to follow. A brass pedagogy text says: “When playing on a double horn, the Bb side of the horn should be tuned first, using a written C. Once the Bb side is in tune, the F side of the instrument should be tuned, ideally to a written C or G.”
• Keep the hand in the bell while you do it. The same source is explicit that “whenever the horn is tuned, the right hand should be in the bell, as hand placement alters the pitch of the instrument”. Tuning with the hand out gives a reading you cannot use.
• Orchestras tune to a concert A given by the oboe. Work out the written note from the fifth relationship rather than trusting a guess — the same written note a fifth above is the way to find it.
• For concert B♭, the written note is F. A written F on the F side sounds concert B♭, matching the instrument’s fundamental.

Adjusting the pitch: slides and the right hand

• The slides set the instrument. Wikipedia’s article on tuning slides notes that a modern double horn has several tuning slides, which are sometimes moved during performance. Brass pedagogy adds that the individual slides for each rotor should also be tuned periodically, not just the main slide. The general rule holds: pulling a slide out flattens, pushing it in sharpens.
• The right hand adjusts pitch continuously. Brass pedagogy: “As horn players play, they primarily adjust their pitch through the manipulation of the right hand.” Opening the bell by pulling the hand away from the flare raises the pitch and brightens the tone; pushing the hand further in or rotating the wrist closes the bell, darkens the tone and flattens the pitch.
• The hand sits in a specific place. The same source describes the relaxed hand, fingers together as if cupping water, resting against the bell wall at around the two o’clock position. The instrument is designed to play sharp and slightly unfocused until the hand tames it.
• Stopped horn changes the fingering. Fully stopping the bell by pivoting the hand forward raises the pitch about a half step, so stopped passages must be fingered a semitone lower. Wikipedia’s hand-stopping article explains the physics: cupping the hand can lower or raise pitch by a semitone or more, and a fully stopped bell shortens the effective tube and raises the pitch by about a semitone for horns near F.
• Blend the two adjustments. Use the slides to put the instrument in the right place and the hand for living, note-by-note intonation. Fighting one with the other leaves the horn unstable.

Common intonation problems by register

• The working register has crowded partials. Brass pedagogy notes that beginning horn players find the middle of their register around the third to sixth partials and can reach several partials quickly — and that the partials are close together there, so they “quickly find themselves a second or third off of their desired pitch”.
• Above third-space C is the recognised trouble zone. Wikipedia’s horn article says that on the F horn, accuracy above third-space C is a concern for most players because they are high in the harmonic series where the overtones are closer together.
• The B♭ side exists for the upper register. Brass pedagogy explains that the B♭ side gives more accurate access to the upper register because its partials are spaced further apart and are typically more in tune, and that B♭ fingerings are used for the middle of the treble staff and above.
• The worst valve combinations are simply avoided. The same source observes that horn players seldom use the 1+3 and 1+2+3 fingerings, which removes many of the sharpest combinations and leaves room to adjust with the hand.
• Dynamics and hand position interact. A crescendo with the hand fixed in one position drifts; the hand and the air move together.
• A cold horn reads flat and feels unstable. Warm up before judging intonation, and remember that the reading will rise as the metal warms.

A short warm-up routine

1. Set posture and hand position before the instrument goes up. Brass pedagogy stresses placing the right hand appropriately and reducing tension with relaxed airflow.
2. Breathing work and long tones, letting the hand sit in its playing position from the first note.
3. Lip slurs across the crowded middle partials, listening for clean partial changes rather than over-blowing.
4. Then tune — the B♭ side first on a written C, then the F side on a written C or G, hand in the bell.
5. Check a high note on the B♭ side before real playing, since that is where accuracy is hardest.

Accuracy and limits

• The display is a perfect fifth below your part. Every reading carries that conversion; a correct-looking F is a written C.
• Hand position changes the reading. Tune with the hand where you actually play, or the result is meaningless.
• Single notes prove little. Check a middle note, a low note and a high note; the two sides of a double horn and the crowded partials mean tendencies differ across the instrument.
• The high register is the hardest to place. Read the display more cautiously there, and treat alternate fingerings and the B♭ side as tools rather than last resorts.
• Room noise and reflections compete. Horn is directional and reflective rooms are unkind; tune in a drier space or use a clip-on tuner in a section.
• A stuck rotor or a leaking water key is a repair. If one side of the horn reads or responds differently from the other, have it checked rather than compensating with the hand.
• The configured range is 25 Hz to 2200 Hz. The horn’s sounding range sits comfortably inside it.

Free, in the browser, no app

If you searched for a french horn tuner app, the browser version removes the install step: this online french horn tuner is free, needs no account, and does no in-app purchase. The audio is analysed locally and never uploaded. On a phone, add the page to your home screen and it opens with one tap.

Safety

• Do not force a stuck rotor or slide. Horn valves and slides are easily bent; if they bind, have them cleaned and serviced.
• Keep the water keys clear. Moisture left in the instrument affects response and can damage the finish and the mechanism.
• Support the instrument properly. The horn is held close to the body and the left hand carries much of its weight; hold it so the hand and wrist are not strained.
• Rest your embouchure. High-register horn playing is tiring; pressing harder against the mouthpiece is a fast route to a sore lip and a worse sound.
• Protect your hearing. The bell points backwards and the sound comes to the player’s own ears quickly; ear protection in section work is sensible.
• Warm up gradually and never force volume. Build from long tones to full dynamics so the embouchure is ready for the range.