Updated November 4, 2026

Bass Tuner

Tune a 4-string, 5-string, or drop D bass guitar online with your phone or computer microphone.

Tunes with your device's microphone. Nothing is recorded or uploaded.

Settings

How to Tune Your Bass

Choose your tuning under Settings: 4-string, 5-string, or drop D.
Tap Start Tuning, then pluck one string at a time and mute the others.
If it says Tune up, tighten the string. If it says Tune down, loosen it. Stop when it shows In tune.

Phone microphones pick up notes below about 50 Hz poorly. The tuner reads the pitch from the string's overtones as well, but hold the phone close to the bass or to the amp's speaker, and pluck firmly.

String Notes and Frequencies

At the standard reference pitch, A4 = 440 Hz. String 1 is the highest-pitched string.

4-String

String	Note	Frequency
4	E1	41.20 Hz
3	A1	55.00 Hz
2	D2	73.42 Hz
1	G2	98.00 Hz

5-String

String	Note	Frequency
5	B0	30.87 Hz
4	E1	41.20 Hz
3	A1	55.00 Hz
2	D2	73.42 Hz
1	G2	98.00 Hz

Drop D

String	Note	Frequency
4	D1	36.71 Hz
3	A1	55.00 Hz
2	D2	73.42 Hz
1	G2	98.00 Hz

Questions

What are the notes on a bass guitar?+

A 4-string bass is tuned E1, A1, D2, and G2, one octave below the lowest four guitar strings. A 5-string adds a low B0 below the E. Drop D lowers the E string to D1.

Why does my phone struggle with the low strings?+

Phone microphones barely pick up sound below about 50 Hz, and the low E is 41 Hz and the low B 31 Hz. The tuner works from the overtones, which is slower, so hold the phone close, pluck firmly, and give it a moment.

Can I tune my bass through an amp?+

Yes. Put the phone near the speaker at a moderate volume, and turn off effects such as chorus or octave pedals first.

Is my audio recorded?+

No. The sound is analyzed in your browser, on your device. Nothing is saved or uploaded.