Online Guitar Tuner
Chromatic microphone tuner — standard and alternate tunings, no app needed.
Microphone off
Tap a string name to hear its reference pitch.
Online guitar tuner — how it works and how accurate it is
Press Enable microphone, allow access when the browser asks, and play one string at a time. The tuner reads the pitch about sixty times a second using autocorrelation, which locks onto the fundamental rather than the loudest harmonic, and reports the nearest note, the measured frequency in Hz and the deviation in cents. A cent is one hundredth of a semitone; anything inside ±5 cents reads as in tune, which is tighter than most players can hear on a single note.
The string that matches what you are playing lights up automatically, so you do not have to select it first. Tap a string label to hear its reference pitch if you would rather tune by ear.
| Note | Frequency (Hz) | MIDI |
|---|---|---|
| E2 | 82.41 | 40 |
| A2 | 110.00 | 45 |
| D3 | 146.83 | 50 |
| G3 | 196.00 | 55 |
| B3 | 246.94 | 59 |
| E4 | 329.63 | 64 |
Alternate tunings included
Pick a tuning from the menu and the string targets change with it. Drop D lowers the sixth string by a whole tone to D2 (73.42 Hz instead of 82.41 Hz). Half-step down moves every string one semitone lower, and DADGAD retunes the first, second and sixth strings for open-tuned playing.
Tuner and metronome in the same session
Tuning and timing are usually the same two minutes of a practice session. Tune here, then open the online metronome in the next tab — or the metronome with time signatures if you are working on a compound meter. For open chord shapes with audio, the guitar chord chart plays each one back.
If the microphone does not work
- The page must be on HTTPS. Browsers block microphone access on plain HTTP.
- If you blocked the prompt by accident, clear the permission from the padlock icon in the address bar and press the button again.
- Only one application can hold the microphone on some systems. Close video-call software first.
- On iOS, Safari needs the tab to be in the foreground for the microphone to stay live.
Frequently asked questions
Why does the tuner sometimes show the wrong note?
Harmonics can confuse pitch detection on certain instruments or in noisy environments. Try plucking closer to the 12th fret for a cleaner fundamental, or move away from background noise sources. The tuner also needs a minimum signal level before it activates.
Can I use this tuner for bass guitar?
Yes. The chromatic detection works across the full audible range, and the standard bass strings E A D G, one octave below the guitar, are detected accurately. The string labels show the closest guitar string but the note name and frequency in Hz are correct.
Does my audio get sent to a server?
No. All pitch processing happens in your browser using the Web Audio API. Your microphone audio never leaves your device, and nothing is recorded or stored.
Do I need to download anything to use this online guitar tuner?
No. It runs in the browser tab you already have open. The only requirement is that the page is served over HTTPS, which browsers demand before granting microphone access, and that you allow the microphone when prompted.