Mic Tuner
Standard 4-string · E1 A1 D2 G2
About the Bass Tuner
Guitar Tool Hub's bass tuner listens to your bass through the microphone and shows how far each open string is from its target, in cents. It is built for the low range of a bass. It detects down to about 26 Hz, below the low B of a 5-string (30.9 Hz), where most guitar tuners stop. Pick one of 9 tunings for 4, 5 and 6-string bass, and the tuner snaps to whichever string you play, or you can lock it onto one string. You can also change the reference pitch from 440 Hz, or turn the mic off and tap a string to hear its exact reference tone. Pitch detection runs in your browser: nothing is recorded or uploaded.
- 01Microphone pitch detection down to about 26 Hz, below a 5-string low B
- 029 tunings: standard 4, 5 and 6-string, Drop D, Drop C, half step down, full step down, BEAD, 5-string high C
- 03Auto string detection, or lock onto one string
- 04Cents needle with an in-tune zone
- 05Adjustable reference pitch, A4 = 415–466 Hz
- 06Reference tone for every string when the mic is off
- 07Runs in the browser, and nothing is recorded or uploaded
Frequently Asked Questions
Press Start tuner and allow microphone access. Pick your tuning, then play one open string and let it ring. The needle shows how many cents the string is off: turn the peg up if it says Tune up, down if it says Tune down, until the needle sits in the green zone. Repeat for every string, then check them all once more.
Yes. The tuner detects pitches down to about 26 Hz, below the low B of a 5-string or 6-string bass (B0, 30.87 Hz) and below Drop C (C1, 32.70 Hz). Many guitar tuners, including the guitar tuner on this site, stop around 60 Hz, which is above a bass's open E (41.20 Hz).
Standard 4-string bass tuning is E A D G, from the thickest string to the thinnest: E1 (41.20 Hz), A1 (55.00 Hz), D2 (73.42 Hz) and G2 (98.00 Hz). A 5-string adds a low B0 (30.87 Hz), and a 6-string adds a high C3 (130.81 Hz).
In auto mode the tuner compares what it hears with every string in the tuning and picks the nearest. A string that is more than about a semitone out of tune can read as its neighbour. Tap that string in the Strings row to lock the tuner onto it, tune it close, then tap it again to go back to auto.
Built-in laptop and phone microphones are weak at low frequencies. Hold the bass close to the microphone and pluck firmly, or plug the bass into an audio interface and pick that as your microphone input. You can also turn the mic off and tap a string to hear its reference tone, then tune by ear.
9 tunings: Standard 4-string (E A D G), Drop D (D A D G), half step down (E flat, A flat, D flat, G flat), full step down (D G C F), Drop C (C G C F), BEAD 4-string (B E A D), Standard 5-string (B E A D G), 5-string high C (E A D G C) and Standard 6-string (B E A D G C).
Yes. The reference pitch can be set anywhere from 415 to 466 Hz, 1 Hz at a time, and every string's target frequency moves with it. The setting is remembered in your browser.
No. Pitch detection runs in your browser, and the microphone signal is never recorded, stored or uploaded. The bass tuner is free, with no account and no download.