What are the notes of Open G tuning?

D G D G B D, from string 6 (nearest your face when you hold it) to string 1.

Can I tune without a microphone?

Yes. Tap any string in the tuner to hear its reference tone and tune by ear until the beating disappears.

Open G tuner

Open G tuning sets the strings, from string 6 to string 1, to D2, G2, D3, G3, B3 and D4. D G D G B D. Keith Richards and slide. From standard tuning, tune the E string down 2 semitones to D, A string down 2 semitones to G and E string down 2 semitones to D. Press Start, play each string and turn the peg until the needle centers.

String notes and frequencies (A4 = 440 Hz)

String 6: D2 at 73.42 Hz
String 5: G2 at 98.00 Hz
String 4: D3 at 146.83 Hz
String 3: G3 at 196.00 Hz
String 2: B3 at 246.94 Hz
String 1: D4 at 293.66 Hz

Questions

What are the notes of Open G tuning?: D G D G B D, from string 6 (nearest your face when you hold it) to string 1.
Can I tune without a microphone?: Yes. Tap any string in the tuner to hear its reference tone and tune by ear until the beating disappears.

Also try: Drop D tuner · Half step down tuner · Whole step down tuner · Guitar Tuner