Guitar Tuner for Teachers

Ten guitars come out of their cases and no two are in tune. A string has slipped on the bus, a new pupil has never turned a tuning peg, and nobody can yet hear whether the note is too high or too low. Onlineguitartuner.app is an online guitar tuner that runs in the browser on the classroom computer, the smartboard or a pupil’s own phone. Open the page, press Start tuner and play an open string. There is no account, nothing to install and no ads.

Open the tuner

What you get

• A microphone tuner for acoustic, electric and classical guitar. Press Start tuner, allow the microphone and play one open string. Auto finds the nearest string, the display shows how many cents you are off and says Too low, Too high or In tune when the needle is in the green zone. You can also pick a string yourself (E 6 to E 1).
• Six tunings. Standard (E A D G B E), Drop D, Half step down, DADGAD, Open G and Open D. Read what they are used for in alternate tunings.
• Reference tones, no microphone needed. Press a string to hear its note, with volume and Repeat every 3 seconds, so pupils can tune by ear.
• More for the lesson: a virtual guitar, guitar chords and a bass tuner for the bass players in the group.

Projector mode

Press Projector mode under the tuner and it fills the screen on a black background, with a very large note name, a large needle and a large cents display, so the whole class can follow from the back of the room. When a string is in tune, the note, needle and cents turn green and a green bar says In tune ✓, so it does not rely on colour alone. The tuning menu and the Auto and string buttons still work. Press Esc or ✕ to leave. If the browser does not allow full screen, the projector view fills the browser window instead. The tuner remembers the setting in this browser only.

Lesson ideas

Tune together on the board

Put the tuner on the projector and let one pupil at a time play an open string while the class watches the needle. Pupils learn to read “too low / too high” before they can hear it.

Which way do I turn?

Beginners often turn the wrong peg or the wrong way. Let a pupil turn slowly while the class calls out whether the needle moves towards the centre. The tuner page’s tip helps here: if a string is sharp, loosen it below the note and tune back up to it, so it holds its pitch better.

Ear first, then check

Play a string with Repeat every 3 seconds, let pupils tune by ear, then check each guitar with the microphone tuner. Over time, the tuner becomes the check rather than the crutch.

Learn the string names

Use the note table on the tuner page (string 6 is the thickest, E2, nearest your face; string 1 the thinnest, E4) as a quick quiz before tuning starts.

Try a new tuning

For older pupils, switch to Drop D or Open G and let them hear how familiar chords change. Remember to tune back to Standard before the next class.

Practice at home

Pupils can open the same page on a phone at home, so they start practice in tune and you know what they are using.

Tips for a noisy classroom

The tuner reads one note at a time, so tune one guitar at a time while the others mute their strings. Play one string, close to the phone or laptop, and let it ring. After all six strings, check them all once more, because the neck settles as the tension changes.

Before your first lesson

The tuner runs in a current browser (Chrome, Edge, Firefox or Safari) on a device with a microphone. The first time, the browser asks for microphone permission; if the class device is managed by the school, the school’s IT may need to allow microphone access for the site. The reference tones work without a microphone.

Privacy

• No account, no login and no pupil data. No ads, analytics or tracking.
• The browser only gives the page microphone access after you allow it. Sound is analysed on the device; nothing is recorded, saved or uploaded, and the microphone switches off when you press Stop or leave the page. See privacy.