Guitar Tuner
Tune one string at a time with your microphone. Choose a tuning, start listening, then adjust until the meter is centered.
Pluck one string and let it ring.
A Guitar Tuner helps you tune each string of a six-string guitar using your device’s microphone. Select your tuning, start the microphone, pluck one open string at a time, and the tuner shows the detected note, frequency, cents offset, and whether the string is flat, sharp, or in tune.
For standard guitar tuning, the open strings from lowest to highest are E2 – A2 – D3 – G3 – B3 – E4. Their approximate frequencies are 82.41 Hz, 110.00 Hz, 146.83 Hz, 196.00 Hz, 246.94 Hz, and 329.63 Hz.
How to Tune a Guitar Online
Start by choosing the tuning you want to use. Standard EADGBE tuning is the default and is the right choice for most six-string guitar practice, lessons, songs, and chord shapes.
Then:
- Press Start Microphone and allow microphone access.
- Pluck one open guitar string.
- Let the note ring briefly.
- Watch the tuner identify the nearest target string.
- Check whether the result says Flat, Sharp, or In Tune.
- Adjust the tuning peg slightly and pluck the string again.
- Repeat the process for all six strings.
For more background on tuning technique, string order, and common beginner mistakes, read the Guitar Tuning Guide.
Pluck only one string at a time. Muting the other strings can help reduce sympathetic vibration and make the reading easier to interpret.
Standard Guitar Tuning: E A D G B E
Standard tuning for a six-string guitar is:
| String | Note | Approx. Frequency |
|---|---|---|
| 6th — lowest/thickest | E2 | 82.41 Hz |
| 5th | A2 | 110.00 Hz |
| 4th | D3 | 146.83 Hz |
| 3rd | G3 | 196.00 Hz |
| 2nd | B3 | 246.94 Hz |
| 1st — highest/thinnest | E4 | 329.63 Hz |
The strings are conventionally described from the lowest-pitched thick string to the highest-pitched thin string as E–A–D–G–B–E.
If you want to study the relationship between notes and their exact frequencies, the musical note frequency chart is a useful reference. You can also read the site’s explanation of how to convert musical notes to frequency in Hz.
How to Read Flat, Sharp, and In Tune
The tuner compares your detected frequency with the target frequency for the selected guitar string.
Flat means the string is sounding below the target pitch. You generally need to raise its pitch by tightening the string carefully.
Sharp means the string is sounding above the target pitch. You generally need to lower its pitch by loosening the string slightly.
In Tune means the detected pitch is close to the target frequency within the tuner’s center tuning range.
Make small adjustments rather than turning the tuning peg aggressively. This is especially important when a string is already close to its target.
What Do Cents Mean on a Guitar Tuner?
The cents reading shows how far your current pitch is from the target note.
One semitone is divided into 100 cents. A negative value indicates that the detected pitch is below the target, while a positive value indicates that it is above the target.
For example:
−12 cents → flat
0 cents → centered on the target
+9 cents → sharp
Cents are useful because two readings can display the same note name while still being noticeably different in tuning.
If you want a more detailed explanation of this measurement, read What Are Cents in Music Tuning?.
Why Guitar Tuners Sometimes Jump Between Notes
A guitar string does not produce only one frequency.
When you pluck a string, its sound contains a fundamental frequency plus harmonics. Research into digital guitar tuners specifically identifies detection of the fundamental frequency of a plucked string as a central tuner-design challenge.
This explains a common problem: a tuner may momentarily react to an upper harmonic instead of the fundamental.
For example, the low E string has a fundamental near 82.41 Hz in standard tuning, but its sound contains higher-frequency components as well. If one harmonic becomes particularly strong, a detector can briefly show a higher note.
Pitch-detection discussions and signal-analysis examples also document octave errors caused by strong second-harmonic content.
For a fuller explanation, read Why Tuners Show Multiple Notes: Harmonics Explained.
Tips for Getting a Stable Tuning Reading
A clean signal makes microphone-based tuning easier.
Try these practices:
- Tune in a reasonably quiet room.
- Pluck one open string at a time.
- Mute strings you are not tuning.
- Avoid hitting the string excessively hard.
- Give the initial pick attack a moment to settle.
- Keep the guitar reasonably close to the microphone.
- Let the note sustain while making small tuning adjustments.
If your tuner repeatedly jumps or fails to settle, see Why Does My Pitch Detector Give Unstable Readings?.
Your microphone also affects the signal reaching the detector. Different microphones and devices respond differently across the frequency spectrum, especially toward lower frequencies. The guide on how microphone quality affects pitch detection accuracy explains why two devices may not behave identically.
Alternate Guitar Tunings
The tuner also supports common alternatives to EADGBE.
Drop D
D2 – A2 – D3 – G3 – B3 – E4
Drop D lowers the sixth string from E2 to D2 while leaving the other five strings at their standard pitches. It is popular because it creates a lower bass range and makes certain power-chord shapes easier.
Half Step Down
All six strings are lowered by one semitone:
Eb – Ab – Db – Gb – Bb – Eb
Drop C
A common Drop C arrangement is:
C – G – C – F – A – D
Open D
D – A – D – F# – A – D
Open G
D – G – D – G – B – D
DADGAD
D – A – D – G – A – D
Alternate tunings change the relationships between open strings, which can create different chord voicings and playing possibilities.
If you frequently switch tunings, make sure you know which preset is selected before making large peg adjustments.
Acoustic vs Electric Guitar Tuning
An acoustic guitar normally produces enough sound for a nearby phone, tablet, or computer microphone to detect an open string directly.
An unplugged electric guitar can also work if the microphone receives a sufficiently strong signal, but results may depend more heavily on the device and room. If necessary, move closer to the microphone or use a clean amplified signal at a moderate volume.
Distortion is not ideal for basic tuning because nonlinear amplification introduces additional harmonic content. Research on distorted guitar signals shows that distortion can generate additional frequency components beyond the played fundamental.
For the cleanest tuner result, use a clean guitar tone whenever practical.
Guitar Tuner Accuracy and Limitations
A browser guitar tuner can provide useful real-time tuning feedback, but its performance depends on the incoming audio.
Factors that can affect a reading include:
- microphone quality
- background noise
- room reflections
- other vibrating strings
- strong harmonics
- weak low-frequency capture
- old or unstable strings
- excessive pick attack
- rapidly decaying notes
The displayed cents and Hz values should be interpreted as tuning guidance rather than proof of laboratory-level measurement accuracy.
Also remember that tuning open strings does not automatically guarantee perfect intonation across the entire fretboard. If open strings are correctly tuned but fretted notes consistently sound sharp or flat, guitar setup or intonation may need attention.
Frequently Asked Questions
What is standard guitar tuning?
Standard six-string guitar tuning is E2 – A2 – D3 – G3 – B3 – E4, from the thickest string to the thinnest.
Which guitar string should I tune first?
There is no requirement to start with one particular string when using a microphone tuner. Many players work from the low E string across to the high E string because the order is easy to remember.
Why does my low E string give unstable readings?
Low-frequency strings can contain strong harmonics, and some microphones reproduce low frequencies less effectively. Let the initial attack settle, mute other strings, and use a clean signal.
What does a negative cents reading mean?
A negative cents value means your pitch is below the target frequency, so the string is flat.
Can I use this tuner for Drop D?
Yes. Select the Drop D preset before tuning. The sixth string target changes from E2 to D2 while the remaining strings retain their standard pitches.
Can I tune an acoustic guitar with a laptop or phone microphone?
Yes, provided the browser has microphone access and the signal is strong and clear enough for detection.
Why does the tuner show the right note but still say sharp or flat?
A note name represents a pitch region. Your string may be closest to that note while still being several cents above or below its exact target frequency.
Does the tuner record my guitar?
The tuning workflow uses microphone input for live browser-based pitch analysis. It does not require creating or uploading an audio recording for the tuning calculation.
For a deeper technical look at online pitch measurement, see Real-Time Browser Pitch Detection Explained.