Online Guitar Tuner
A free, accurate chromatic tuner you can use right in your browser. Tune your guitar, bass, ukulele or any instrument with your microphone — no download required.
Guitar
Audio is processed entirely on your device — nothing is uploaded or recorded.
How to use the online tuner
- Tap “Start tuning” and allow microphone access when your browser asks.
- Play a single open string or note close to your device.
- Read the note name in the centre and watch the needle.
- Tune up or down until the needle is centred and the display turns green.
Standard guitar tuning (EADGBE)
Most players start with standard tuning. From the lowest, thickest string to the highest, thinnest string the notes are E, A, D, G, B and E:
- 6th string — E2 (low E)
- 5th string — A2
- 4th string — D3
- 3rd string — G3
- 2nd string — B3
- 1st string — E4 (high E)
Pluck each string in turn and adjust the tuning peg until the tuner shows the correct note with the needle centred. A reading to the left means the string is flat (tune up); a reading to the right means it is sharp (tune down).
Frequently asked questions
Is this online guitar tuner free?
Yes. The tuner is completely free, with no download or sign-up required. It runs in your browser on both mobile and desktop.
Does the tuner work on my phone?
Yes. It is mobile-first and works in modern mobile browsers such as Safari on iOS and Chrome on Android. You’ll need to allow microphone access and be on a secure (https) connection.
Can I tune instruments other than guitar?
Absolutely. It is a chromatic tuner, so it works for guitar, bass, ukulele, violin, mandolin, banjo and even your voice.
What is standard guitar tuning?
Standard guitar tuning is E A D G B E from the lowest (thickest) string to the highest (thinnest) — that is E2, A2, D3, G3, B3 and E4.
Why isn’t the tuner detecting my note?
Make sure you have allowed microphone access, play a single note clearly, reduce background noise and move a little closer to the mic. Let the note ring so the tuner can lock onto the pitch.
