Online guitar tuner
Tune by microphone, in cents. Guitar, bass, ukulele and more — Standard, Drop D, Open G, DADGAD and a dozen other tunings.
Turn the microphone on, then play one open string
Audio stays in your browser: nothing is recorded, stored or uploaded.
How to tune your guitar with this tuner
- 1
Pick your instrument and tuning
Choose electric or acoustic guitar, bass, ukulele, mandolin or banjo, then the tuning you want — Standard, Drop D, Open G, DADGAD or half step down. The tuner targets the open strings of that tuning, so a Drop D player tunes the 6th string to D2 rather than to a very flat E2.
- 2
Turn on the microphone
Press the microphone button and allow access when the browser asks. Nothing is recorded or uploaded — the pitch is worked out in the page and thrown away.
- 3
Play one open string
Start with the thickest string and play it on its own, without fretting anything. The tuner picks the open string your note is closest to and names it.
- 4
Read the needle
The needle left of centre means the string is flat and has to come up; right of centre means it is sharp and has to come down. The number underneath is the distance in cents — a hundredth of a semitone.
- 5
Turn the peg slowly
Small movements. If the string is sharp, drop below the note and come back up into it: finishing on a rising turn takes the slack out of the peg and holds the tuning longer.
- 6
Hold it, then move on
Keep the note inside the green zone for about a second and the string is marked green. Work through every string, then play the first one again — tightening the others will have pulled it flat.
Tuning questions
How do I tune a guitar with this tuner?
Pick your tuning, turn on the microphone, and play one open string at a time. The tuner names the string it hears and shows how far off it is in cents: needle left means flat and needs tightening, needle right means sharp and needs loosening. Hold the note in the green zone for a second and that string is done, then move to the next one.
Is an online tuner accurate enough?
Yes for everyday playing. Pitch is measured against the equal-tempered reference of A4 = 440 Hz and read out in cents, and the green zone is ±10 cents — tighter than most players can hear on a single string. The limit is the microphone and the room, not the maths: a noisy room or a laptop microphone two metres away will make the reading jump around.
Do I need an audio interface, or will my laptop microphone do?
A built-in laptop or phone microphone is fine for an acoustic guitar, and fine for an electric played unplugged. If you have an audio interface, plugging the guitar straight in gives a much steadier reading because the tuner hears the string instead of the room.
Why does the tuner show the wrong note?
Two usual causes. The string is so far out that it is genuinely closer to a different open string — check you are playing the string you think you are. Or the microphone is picking up the string's harmonics rather than its fundamental, which happens most on the low E and B strings; play the note nearer the bridge, a little softer, and let it settle before reading the needle.
How do I get into Drop D?
Select Drop D above, then lower only the thickest string until the tuner reads D2 — every other string stays at standard pitch. A quick check by ear: the open 6th string should now sound an octave below the open 4th (D) string.
Does this work for bass and ukulele?
It does. Bass in four and five strings, ukulele in standard re-entrant, low G, baritone and D tuning, plus mandolin and 5-string banjo. Pick the instrument first and the tuning list changes with it.
Can I tune without a microphone?
Yes — tap any string name under the needle and it plays that pitch, so you can tune by ear against the reference tone. Useful in a loud room, or on a device where microphone access is blocked.
Is my audio recorded or sent anywhere?
No. The microphone stream is analysed inside your browser and never leaves the page: nothing is recorded, stored or uploaded. Closing the tab or pressing stop releases the microphone.
How often should I retune?
Every time you pick the instrument up, and again after ten minutes of hard playing. New strings drift for their first few hours, and so does any guitar that has been moved between a cold car and a warm room.
In tune. Now make the practice count.
Riff Quest is the practice tracker this tuner comes from: the same pitch detection listens while you play, scores what you actually hit, and turns your sessions into a record of how you are improving. It is free — no subscription, no paywall.