Music & audio / Runs in your browser
Free online guitar tuner with 10 tunings (bass and ukulele too)
Play a string, watch the needle. Standard, drop D, open G, DADGAD, half and full step down, 4-string bass, ukulele, or any note chromatically.
- Free, no account
- Uses your microphone
Audio is analysed live in this tab and never recorded or sent anywhere.
How it works
- 01
Pick your tuning. Standard is selected by default; the strings of the chosen tuning appear as cards on the right.
- 02
Press Start tuner and allow the microphone when the browser asks. Nothing is recorded: the signal is analysed frame by frame and thrown away.
- 03
Play one string and let it ring. The tuner locks onto the nearest string of the tuning, the needle shows how far off you are in cents, and the card lights green when you are within five cents.
- 04
Tap any string card to hear a plucked reference at the exact target pitch, and adjust the A4 reference if you play with an orchestra or at 432 Hz.
Questions
How accurate is it?
The detector is the YIN algorithm with parabolic interpolation, reading at a halved sample rate, and readings are median-smoothed over five frames. In a quiet room it resolves well under one cent; "in tune" is called at five cents, which is about the smallest melodic difference people can hear.
Why does it not pick up my low E or bass strings?
Play the string on its own and let it ring rather than strumming. Low strings need a moment for the fundamental to settle, and the tuner waits for a clear, periodic signal before it commits. Make sure the right microphone is selected and not muted, and that the input level bar moves when you play.
Can I tune without a microphone?
Yes. Every string card plays a synthesised plucked reference at the exact target frequency for the chosen A4, so you can tune by ear the way you would with a tuning fork.
Does the tuner work for bass and ukulele?
It does. The Bass preset covers a 4-string bass (E A D G) with a detection window that reaches down to 30 Hz, and the Ukulele preset covers G C E A re-entrant tuning. Chromatic mode names any note from 30 Hz to 2 kHz with its octave.