12NOTEZ · Free Tool
Tune your bass guitar with your mic — Standard — E A D G. Free, accurate, private.
Your audio never leaves your device — detection runs entirely in your browser.
Music teachers, bloggers and band sites: paste this snippet to embed the tuner anywhere.
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A 4-string bass is tuned E A D G — the same as a guitar's lowest four strings, one octave lower. Because the notes are so low, play firmly and give the needle a moment to lock on.
E1A1D2G2
| Tuning | Notes |
|---|---|
| Drop D | D A D G — lower the E string a whole step |
| 5-string (low B) | B E A D G — adds a low B below standard |
| Half-step down | Eb Ab Db Gb — to match Eb-tuned guitars |
Switch the instrument selector above to chromatic mode to tune to any of these notes by ear.
Standard bass guitar tuning is Standard — E A D G — strings E1, A1, D2, G2 from lowest to highest.
Allow mic access and play the low E string open. Match E1, then A1, D2 and finally G2. Match each string to the needle until it reads in-tune (green).
From low to high, the strings are E1, A1, D2, G2.
Yes — this tuner uses your device microphone with cents-precise pitch detection, runs entirely in your browser, and your audio never leaves your device.
Prefer to set tempo instead? Try the free online metronome, or find any song's key in our database.