🎸 Online Guitar Tuner
Tune all 6 strings using your microphone. Shows note, frequency and cents deviation in real time.
🎸 Standard Tuning Reference (E-A-D-G-B-e)
E
82.4 Hz
String 6
A
110 Hz
String 5
D
146.8 Hz
String 4
G
196 Hz
String 3
B
246.9 Hz
String 2
e
329.6 Hz
String 1
✅ How to Use This Guitar Tuner
- Tap START and allow microphone access when your browser asks.
- Hold your guitar close to the microphone and pluck a single string.
- The tuner shows the detected note, its frequency in Hz, and how many cents off-pitch it is.
- The needle points left if the string is flat (↓), right if sharp (↑), and centres when in tune.
- Use Chromatic mode to detect any note automatically, or switch to By String mode to tune one string at a time.
- Tune each string until the needle is centred and the display turns green.
Common Questions
Does this work on mobile?
Yes — the tuner works on iPhone and Android. Make sure you grant microphone permission when prompted. For best results on mobile, use in a quiet room and hold the guitar body close to the phone microphone.
What is a "cent" in music tuning?
A cent is 1/100th of a semitone. There are 100 cents between any two adjacent notes. A string is considered in tune when it is within ±5 cents of the target pitch. More than ±10 cents will sound noticeably out of tune.
What is standard guitar tuning?
Standard tuning is E-A-D-G-B-e from the thickest (6th) string to the thinnest (1st). The low E string vibrates at 82.4 Hz, and the high e at 329.6 Hz. This is the most common tuning for acoustic and electric guitar.
Why isn't the tuner picking up my guitar?
Common reasons: background noise is interfering, the microphone permission was denied, or the guitar is too far from the microphone. Try tuning in a quiet room, plucking the string firmly, and holding the guitar body close to your device's mic.
What is the difference between Chromatic and By String mode?
Chromatic mode detects any note you play and shows the nearest pitch — useful for quick checks and alternate tunings. By String mode locks the target to one specific guitar string so you can tune each one precisely without the display jumping to nearby notes.
How accurate is this tuner?
The pitch detection uses an autocorrelation algorithm (the industry standard for browser-based tuners) with A4 = 440 Hz reference. Accuracy is typically within ±1–2 cents, which is sufficient for all standard playing. Professional recording may require a hardware tuner pedal.
Guitar String Frequencies
| String | Note | Frequency | Octave | If flat, tune... |
|---|---|---|---|---|
| 6 (thickest) | E | 82.41 Hz | E2 | Tighten (turn peg away from you) |
| 5 | A | 110.00 Hz | A2 | Tighten |
| 4 | D | 146.83 Hz | D3 | Tighten |
| 3 | G | 196.00 Hz | G3 | Tighten |
| 2 | B | 246.94 Hz | B3 | Tighten |
| 1 (thinnest) | e | 329.63 Hz | E4 | Tighten |
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References & Notes
- Pitch detection uses the autocorrelation algorithm — the same method used in most browser-based tuners.
- Reference pitch: A4 = 440 Hz (international standard).
- Standard tuning frequencies: E2 (82.41), A2 (110.00), D3 (146.83), G3 (196.00), B3 (246.94), E4 (329.63) Hz.
- No audio is recorded or transmitted — all processing happens locally in your browser.