Acoustic Guitar Tuner
Tune a steel-string acoustic guitar with the microphone on your phone or computer. It starts in standard EADGBE, and drop D, open G, DADGAD and every other tuning are one click away.
- Free, no sign-up
- Works with any built-in mic
- Auto string detection
- Private, on-device
Reference pitch (A4)
Hz
Lower it in noisy rooms
Press Start tuning, then play a string
0/6 tuned
Standard notes
A4 = 440 Hz| String | Note | Frequency |
|---|---|---|
| 6 | E2 | 82.41 Hz |
| 5 | A2 | 110.00 Hz |
| 4 | D3 | 146.83 Hz |
| 3 | G3 | 196.00 Hz |
| 2 | B3 | 246.94 Hz |
| 1 | E4 | 329.63 Hz |
Tuning an acoustic guitar
An acoustic guitar is loud enough for any phone or laptop microphone, so you don’t need a clip-on tuner. Hold the soundhole 20–50 cm from the mic and pluck one string at a time.
Fingerstyle and folk players often use drop D, DADGAD or open G. Pick one from the menu and the target notes change to match.
Keyboard shortcuts
- Space Start or stop the microphone
- 1–9 Play a string’s reference note
- M Switch Auto / Manual mode
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Start the tuner
Press Start tuning and allow access to the microphone. Hold your acoustic guitar 20–50 cm from the mic.
-
Play one string
Pluck one string and let it ring. Auto mode shows the closest string. To stay on one string, switch to Manual.
-
Adjust the tuning peg
If the needle is on the left, tighten the string to raise the pitch. If it is on the right, loosen it. Stop when the needle is in the middle and turns green.
Frequently asked questions
Can I tune an acoustic guitar with my phone?
Yes. Open this page on your phone, press Start tuning and allow the microphone. The built-in mic hears an acoustic guitar easily, so you don’t need an app or a clip-on tuner.
Why does my acoustic guitar go out of tune?
Changes in temperature and humidity make the wood and strings move. New strings stretch for a few days, and worn tuning machines can slip. Tune every time you pick it up, and let a cold guitar warm up to room temperature first.
Should I tune up or down to the note?
Always finish by tuning up to the note. If a string is sharp (too high), loosen it below the note and then bring it back up, so the gears hold the tension.
Do acoustic and electric guitars use the same tuning?
Yes. Both use standard tuning, E A D G B E (E2 A2 D3 G3 B3 E4), unless you choose an alternate tuning.
All guitar tunings
Standard & down-tuned
Drop
Open
Alternate
7-string
8-string
12-string & guitalele
More tuners
- Bass Tuner 4, 5 and 6-string bass, from drop D to BEAD. E A D G
- Ukulele Tuner Soprano, concert, tenor and baritone ukulele. G C E A
- Violin Tuner G D A E with bowed reference tones. G D A E
- Viola Tuner C G D A, a fifth below the violin. C G D A
- Cello Tuner C G D A, an octave below the viola. C G D A
- Double Bass Tuner Upright bass in orchestral and solo tuning. E A D G
- Banjo Tuner Open G, double C, sawmill, tenor and Irish tenor. G D G B D
- Mandolin Tuner Mandolin, mandola and octave mandolin. G D A E
- Chromatic Tuner Any instrument or voice, with B♭/E♭/F transposition.
Music tools
- Metronome Accurate online metronome with accents and subdivisions.
- Tone Generator Play any frequency from 20 Hz to 20 kHz.
- Tuning Fork 415, 432, 440, 442 and 444 Hz forks.
- Pitch Detector See the exact note and frequency you play. C
- Custom Tuning Tuner Build any tuning with 3 to 12 strings. E A D G B E
- Tune Guitar by Ear Repeating reference notes for every string. E A D G B E