Fretnook / Free tools / Guitar Tuner
Open to everyone · no sign-up

Free online guitar tuner

Press Listen, play a string, and watch the needle. Fretnook's chromatic tuner reads your microphone in real time and covers standard tuning plus five alternate tunings, with nothing to install and no account.

Open to everyone — no sign-up. Your microphone audio is analysed in your browser and is never uploaded.
Quick start

Tune your guitar in four steps

  1. Allow the microphone

    Open the tuner and press Listen in the top-right corner. Your browser asks for microphone permission the first time; allow it. With a USB microphone or audio interface, choose it from the Default microphone menu beside Listen.

  2. Choose your tuning

    Pick Standard, Drop D, Whole Step Down, Open G, Open D or Open E from the Tuning menu. Tap any string button to hear its reference note if you would rather tune by ear first.

  3. Play one string and let it ring

    Play a single note, not a chord, and let it sustain. The wheel shows the note name, its frequency in hertz, and how many cents sharp or flat it is.

  4. Turn the peg until the needle turns green

    The needle swings left or right of centre to show sharp or flat. It turns green within about 6 cents of perfect pitch and red outside that.

What you get

A tuner that goes beyond standard tuning

Cents-accurate readout

Note name, frequency in Hz and the offset in cents, updated live while the string rings.

Six guitar tunings

Standard, Drop D, Whole Step Down (D G C F A D), Open G (D G D G B D), Open D (D A D F# A D) and Open E (E B E G# B E).

String targets and reference tones

Tap a string to hear its target pitch. The tuner also shows which string you are closest to and how far off it is.

Any input you have

Built-in microphone, USB microphone or audio interface. A level meter beside the input menu confirms you are getting signal.

Remembers your tuning

Your tuning choice is saved in your browser, so the tuner opens the way you left it.

Works without internet

Install Fretnook from your browser and the tuner keeps working offline, handy in a rehearsal room or backstage.

Tips for a steadier reading

Pluck at a moderate volume and let the initial attack fade for a second. The pitch settles after the pick noise, and that is the reading you want to trust. Hitting a string very hard makes it briefly sharp, so a gentle, even pluck gives the most stable needle.

Tune up to the note whenever you can. If you overshoot, drop the string below the target and bring it up again, which takes the slack out of the tuning peg and helps the string stay in tune.

Work in a fairly quiet room and keep the microphone reasonably close to the guitar. If the needle jumps around, check the level meter beside the microphone menu and make sure only the string you are tuning is ringing; mute the others with your palm.

Which tuning should I pick?

Standard (E A D G B E) suits most songs. Drop D lowers the sixth string one whole step to D, which makes heavy power chords easy to play with one finger. Whole Step Down tunes every string down two semitones (D G C F A D), which is common in rock and helps with vocal range.

Open G, Open D and Open E tune the open strings to a chord, so strumming with no fingers down rings a full chord. They are popular for slide guitar and blues. Pick the tuning first, then tap each string button to hear its target.

Questions

Frequently asked questions

Is this guitar tuner really free?
Yes. The tuner and the Ear Trainer are open to everyone with no account. The rest of Fretnook unlocks with a free email sign-up.
Do I need to download anything?
No. It runs in your browser. If you like, you can install it as an app from your browser menu so it also works offline.
Why is the needle not moving?
Press Listen first, then check that your browser allowed the microphone (a blocked-microphone icon appears in the address bar if it did not). Play a single note and watch the level meter beside the microphone menu to confirm signal is arriving.
How accurate is it?
The needle turns green when you are within about 6 cents of the target, and the readout below it shows the exact frequency and cents offset, so you can tune much closer than that if you want to.
Can I use it for other instruments?
The needle is chromatic, so it shows the nearest note for whatever you play. The string buttons and reference tones are set up for the guitar tunings listed above.
Does Fretnook record or upload my sound?
No. Microphone audio is analysed in your browser. See the privacy notice for exactly what is stored.
More free tools

Keep going in the same rack

Tune up in a few seconds.

Fretnook is free and runs in your browser. Your microphone audio and recordings stay on your device.

● Open the tuner