Online guitar tuner

To tune your acoustic guitar automatically:

• Select the "Auto" mode to automatically tune your guitar. Make sure the microphone access is granted.
• Bring your guitar closer to the microphone so the tuner can recognize the string you're playing.
  The guitar tuner will try to automatically identify the string and provide tuning recommendations.

To tune your acoustic guitar by ear:

The app contains the sounds of strings which correspond to the sounds of a guitar tuned to original tonality.
To tune any string, select the corresponding button on the tuner:

To ensure that the guitar sounds properly, all the strings of a guitar must sound the same as the sounds produced by the tuner.

If you want to manually tune your guitar, the 1st string (Mi or E, i.e. the lowest one) can be tuned with the aid of a tuning fork, another instrument, or other methods.