Online Tuner

How to use the online tuner

This online tuner is chromatic: it names whichever of the 12 notes is closest to the sound it hears, so it works for any instrument, including horns, flutes, harmonicas, pianos and your voice. Press Start tuner and allow the microphone when the browser asks. Your microphone is analysed on this device and is never recorded or sent.

Play one note and let it ring. The big letter is the nearest note with its octave number (A4 is the A above middle C), the line under it says how far off you are in cents, and the small line shows the frequency you played and the exact frequency of the note. The words under the needle tell you what to do: Flat: tune up or Sharp: tune down.

On a computer, Space starts and stops the tuner. Press Sharps or Flats to choose how the black-key notes are named (C# or Db). Need a note to tune to by ear? Pick an octave under Reference tone and tap a note to hear it.

Play a clarinet, saxophone, trumpet or horn? Set Show notes for to Bb, Eb or F instrument and the tuner names the note as written in your part, not the concert pitch. The transposition chart explains how each instrument transposes.

What the needle and the cents mean

A cent is one hundredth of a semitone, the step from one piano key to the next. So 100 cents is a semitone, and 50 cents is halfway to the next note. The needle runs from −50 on the left (flat, too low) to +50 on the right (sharp, too high). Inside the green zone, within 3 cents of the note, the reading turns green; hold it there a moment and it says In tune with a check mark.

When you play far from any note, the tuner jumps to whichever note is nearer, so a string that is 60 cents flat of A reads as 40 cents sharp of G#. If the letter is not the one you expect, turn the peg until the right letter appears, then fine tune with the needle.

It is common practice to come up to the pitch from below. If you go past it, drop below and come back up; the string or slide then settles against the tension instead of slipping back.

Why A4 is 440 Hz

Tuners need a reference, and the usual one is A4 = 440 Hz: the A above middle C vibrates 440 times a second. A conference in London in 1939 recommended it, and the International Organization for Standardization adopted it, first as a recommendation in 1955 and then as the standard ISO 16 in 1975. Not everyone plays exactly there: in continental Europe, A4 commonly sits anywhere from 440 to 444 Hz. If your band, choir, orchestra or piano uses another A, set the A4 box to match (415 to 466 Hz). Every tuner on this site reads the same saved value on this device, so a string section or a band can share it.

Tuning by fifths and beating

Violin, viola, cello and mandolin strings sit a perfect fifth apart, and many string players finish tuning by ear. Bow two neighboring open strings together and listen: an exact fifth sounds calm, and a slightly wrong one has a slow pulse, called beating, that slows down as you get closer and stops when the fifth is pure.

This tuner uses equal temperament, where every fifth is about 2 cents narrower than a pure fifth. The gap adds up across the strings: tune pure fifths down from A and the second string below it sits about 4 cents under the needle's center, the third about 6 cents under. Both results are fine. Choose one method and keep to it for the session.

Note frequencies in the middle octave

Every note is a fixed ratio from A4: one semitone up multiplies the frequency by the twelfth root of 2 (about 1.0595), and an octave up doubles it. These are the notes from middle C to the B above it when A4 = 440 Hz. Divide by 2 for the octave below, multiply by 2 for the octave above.

Tips and a tuner for each instrument

• Play one note at a time. A chord has several pitches, and the tuner can only read one.
• Get close to the microphone and keep the room quiet. A fan, a TV or other players can pull the reading around.
• Let the note settle. The first moment of a plucked or blown note is often a little sharp, so read the needle once the note is steady.

Because this tuner online runs in your browser, it also works on a borrowed laptop or a school computer with nothing to install. For a stringed instrument, the dedicated pages are quicker: they show the strings and pick the one you play. There is a guitar tuner with nine tunings, a bass tuner for four and five strings, a ukulele tuner, the bowed strings (violin, viola, cello), a banjo tuner and a mandolin tuner. Wind players have a flute tuner and a tuba tuner with tuning notes. To watch your voice over time rather than one note, use the pitch detector.

More for band instruments: Clarinet Fingering Chart · Saxophone Fingering Chart · Trumpet Fingering Chart · French Horn Fingering Chart · Euphonium Fingering Chart · Mellophone Fingering Chart · Transposition Chart

Questions

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