Online tuner: play one string and see which way to tune
Open Tuner in the app, allow microphone access and play one string at a time. The screen shows the note it hears and a needle pointing away from the target: left means flat, so raise the pitch slightly; right means sharp, so lower it. When the needle settles near the centre and the note turns green, play the string again to check that the reading stays steady.
Tuner
Flat0
cents+50
Sharp
Sound is analysed on this device. No audio is recorded or uploaded.
Tune one string in three steps
- Choose Tuner on the app's home screen. The first time, allow the browser to use your microphone; on a phone, open the site over HTTPS. A moving waveform beside the microphone shows that sound is reaching the app. If the waveform moves but no note appears, the sound has no clear pitch yet.
- The first-use preset is All, which listens for any single pitched note. Choose Guitar, Bass, Ukulele or Violin to see its standard open strings; your choice is remembered. Auto follows the closest string, or you can select a target such as E2 or A2 yourself.
- Play one string without a chord, voices or another instrument sounding nearby. Turn the tuning peg a little, then play again and watch the needle. Read the steadier part of the sound, not only the first attack. A faded note is the last accepted reading, not a live measurement.
What does the ±50 cents scale mean?
A cent is one hundredth of a semitone. The scale runs from −50 cents (flat) through zero (in tune) to +50 cents (sharp). In the illustration, guitar E2 is about 8 cents flat, so its pitch needs to rise slightly. The needle and colour help you find the direction quickly; confirm the result by getting a repeatable reading near the centre.
Standard guitar strings are E2, A2, D3, G3, B3 and E4. Bass, ukulele and violin show their own open strings when selected. All can check a single note on another instrument or help identify a note; if you are working out a melody from a recording, see how to learn a song by ear. In Settings, the A4 reference can be changed from the default 440 Hz to 430–450 Hz. Check the reference used by the other players before tuning for an ensemble.
The microphone hears sound, but there is no note
Play a clear, sustained single note closer to your device's microphone. Pick noise, string knocks, chords and background sound can make the pitch hard to identify. An unplugged electric guitar may be too quiet for a phone microphone; use an amplifier at a moderate volume and play one string at a time. A very soft decay or strong overtones may also leave a waveform without a stable note.
If the app says the microphone is blocked, allow access in this browser's site permissions, then return and choose Retry microphone. Once the browser has remembered a denial, retrying may not show the permission prompt again until you change that setting. The tuner analyses sound on your device; it does not record or upload audio.
Frequently asked questions
Do I need to download anything or create an account?
No. Open the app in your browser and choose Tuner. You only need to allow microphone access when asked.
Can I play a chord while tuning?
Play one string at a time. Several notes together create a mixed signal, so a single-note pitch reading may be unstable.
Why is the needle still showing an old note, but faded?
It holds the last accepted reading so you can look after the string stops. A faded reading is not live. Play the same string again and wait for a fresh reading before adjusting further.
Choose a string, open Tuner from the app, allow your microphone and play the string on its own. The image above is static; live tuning happens in the app.