Guitar & String Instrument Tuner
Tune your guitar, bass, ukulele, violin, viola, or cello — by mic or by ear. Free, no sign-up needed.
Detects pitch using your microphone.
Press the button to allow microphone access.
Audio data is processed entirely on your device and is never sent to any server.
About This Tuner
This string instrument tuner is a free online tuner that works entirely in your browser. No app download or sign-up required — start tuning right away on your smartphone or computer.
Supported instruments: Guitar (6-string), bass (4-string and 5-string), ukulele, violin, viola, and cello.
Two tuning modes: Mic tuning automatically detects pitch using your device's microphone, while ear tuning plays a reference tone so you can match by ear.
The reference pitch is adjustable from A=430 Hz to 450 Hz, making it suitable for orchestras, concert bands, and other ensembles with different pitch standards. All audio data is processed locally on your device and is never sent to any server.
Supported Instruments & Standard Tunings
Guitar (6-string)
- Standard: E2 A2 D3 G3 B3 E4
- Half Step Down: Eb2 Ab2 Db3 Gb3 Bb3 Eb4
- Drop D: D2 A2 D3 G3 B3 E4
- Open G: D2 G2 D3 G3 B3 D4
- DADGAD: D2 A2 D3 G3 A3 D4
Bass (4-string)
- Standard: E1 A1 D2 G2
- Half Step Down: Eb1 Ab1 Db2 Gb2
- Drop D: D1 A1 D2 G2
Bass (5-string)
- Standard: B0 E1 A1 D2 G2
- Half Step Down: Bb0 Eb1 Ab1 Db2 Gb2
Ukulele
- Standard: G4 C4 E4 A4
- Low-G: G3 C4 E4 A4
Violin
- Standard: G3 D4 A4 E5
Viola
- Standard: C3 G3 D4 A4
Cello
- Standard: C2 G2 D3 A3