Guitar tuner online
Pluck an open string, and the needle tells you whether to tighten or loosen it.
The sound isn't recorded and never leaves your device.
- EString 6
- AString 5
- DString 4
- GString 3
- BString 2
- EString 1
Tap Start tuner. Your browser may ask for permission to use the mic.
Standard tuning, with A at 440 Hz.
How to use it
- Choose Guitar (standard) or Chromatic, tap Start tuner and allow the mic when your browser asks.
- Pluck one open string at a time, close to the mic.
- If it says flat, tighten the string; if it says sharp, loosen it.
- When you see In tune, move on to the next string, and tap Stop when you're done.
How it works
The tuner uses your mic only after you tap Start tuner and your browser gives permission. The sound is analyzed in your browser: it isn't recorded, stored or sent anywhere. Tap Stop, leave the page or close the tab, and the mic turns off.
To find the pitch, it uses YIN, a pitch detection method published in 2002. It reads short windows of sound and drops each one once it's read.
Then, with A at 440 Hz, it picks the nearest string or, in Chromatic, the nearest note. The needle goes from −50 to +50 cents, hundredths of a semitone; within 5 cents, you'll see In tune. When the string fades, the needle dims and keeps the last reading for a moment.
Example
Your cousin hands you his guitar at a campfire, and the 5th string sounds off. You start the tuner and pluck it open: it shows A, 108.0 Hz and −32 cents. The tuner says “It's flat: tighten the string.”
You turn the tuning peg a little at a time until it reads 110.0 Hz and In tune appears. Then you move on to the 4th string. These are the notes of standard tuning:
| String | Note | Frequency |
|---|---|---|
| 6th | E2 | 82.4 Hz |
| 5th | A2 | 110.0 Hz |
| 4th | D3 | 146.8 Hz |
| 3rd | G3 | 196.0 Hz |
| 2nd | B3 | 246.9 Hz |
| 1st | E4 | 329.6 Hz |
Frequently asked questions
How do I tune my guitar with my phone?
Open this page on your phone, tap Start tuner and allow the mic. Then pluck each open string and follow the needle until it says In tune.
What are the notes of standard guitar tuning?
From the 6th string to the 1st: E2, A2, D3, G3, B3 and E4. The 6th is the thickest string and the 1st is the thinnest.
Does the tuner record my guitar?
No. The sound is analyzed in your browser while the tuner is on: it isn't recorded, stored or sent anywhere.
Why can't the tuner hear my guitar?
The mic may be blocked or missing, and the tuner tells you what to check. If it says Listening, move the guitar closer and pluck one string: a chord gives it no clear note.
Why does the tuner show the wrong string?
It shows the string closest to the sound it hears. If it shows a lower string than the one you plucked, yours is far too loose: tighten it. If it shows a higher one, loosen it.
Can I use it for drop D, other tunings or a 7-string guitar?
Yes: choose Chromatic above the tuner, and you'll see the nearest note and its octave, in any tuning. In drop D, the 6th string goes down to D2, at 73.4 Hz. On a 7-string guitar, the 7th string is B1, at 61.7 Hz.
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