Free Online 5-String Bass Tuner
Five targets down to a 31 Hz low B, each string read against its own note.
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Left to right: 5th string, the thickest, to 1st, the thinnest. Tune one string at a time.
Allow microphone access to begin
How to use this tuner
Click Start Tuning and allow microphone access. Play one open string at a time, and the tuner shows how sharp or flat you are from that string’s target in cents. Tap a string button to hear the note and lock the tuner to it.
The bar spans −50 to +50 cents. Zero is perfectly in tune. A low bass string is sharp at the attack and takes a second or more to settle, so read the flat part of the history line, not the first reading.
The tuner reads against the nearest open string of 5-string standard tuning (B0, E1, A1, D2, G2), so the cents value is the distance to that string, not to the nearest chromatic note. Tap a string to hear its reference pitch and lock the tuner to it; tap again to release.
Bass Guitar is already selected. The bass is a concert-pitch instrument written an octave above where it sounds, so the tuner shows the sounding octave: B0, E1, A1, D2, G2. Changing the dropdown turns string mode off; tapping a string turns it back on.
Default is A440. Tap + / − to match a recording or another instrument that cannot be adjusted.
Standard 5-string bass tuning is B0, E1, A1, D2, G2: a 4-string bass with a fifth string a perfect fourth below the E. The low B sounds at 30.87 Hz, which is below the range of most laptop speakers, many headphones, and a fair number of phone microphones. That is the whole difficulty of tuning a 5-string with a microphone: the fundamental arrives weakly, the second harmonic at B1 arrives strongly, and a tuner that picks the strongest peak will happily report the octave. This page reads each string against its own target and, with the B0 button tapped, ignores every other target, so a harmonic cannot pull the reading onto another string.
To give the tuner a fundamental to work with, pluck the B string firmly with a fingertip over the end of the fingerboard rather than with a pick at the bridge, and let it ring. The first second of a low bass note is genuinely sharp, the string is displaced further and vibrates at a slightly higher frequency until the amplitude drops, and the history line shows this as a hook at the top that settles into a plateau. The plateau is the pitch. If the note display flickers between octaves before settling, wait it out; if it never settles on B0, the microphone is not picking up the fundamental, and using a direct signal into the computer, or tuning the B by comparing its fifth-fret harmonic with the open E, is more reliable.
String choice decides whether a low B reads clean or flabby. A .125 or .130 B string at 34 inch scale is typical; lighter than that and the string is slack, wanders in pitch after every note, and reads unsteady on any tuner. Basses with 35 inch scales exist largely to tighten the B. If the open B reads zero but the twelfth-fret note is sharp, the saddle needs to move back; on a B string this intonation error is often larger than on the other strings because the string is so thick, and it will make every fretted note on that string read sharp regardless of tuning.
Most 5-string players stay in standard and use the B for range rather than for drop tunings, but a 5-string in drop A, with the B lowered a whole step to A0, is common in heavier styles and pushes the fundamental to 27.5 Hz, below the tuner’s lower limit on some microphones. Tune the other four strings to this page and the A0 by its octave harmonic against the open A1. For a 4-string in drop D, use the bass drop D page, and for standard 4-string EADG, the bass guitar tuner.
Frequently asked questions
What is standard tuning on a 5-string bass?
B0, E1, A1, D2, G2 from the lowest string to the highest. It is a 4-string bass plus a fifth string a perfect fourth below the E. Some players instead add a high C3 above the G (E A D G C), which the chromatic tuner handles.
Why does the tuner show B1 instead of B0 on my low string?
The fundamental of a low B (30.87 Hz) is weak and its octave harmonic is strong, so the tuner may briefly lock onto B1. Pluck over the fingerboard, wait for the note to settle, and tap the B0 button to lock the tuner to that target.
Can I tune my 5-string bass by ear against the other strings?
Yes. The fifth-fret harmonic on the B string should match the open E string. Once the E, A, D, and G are in tune with the tuner, matching the B by harmonic is a reliable check when a microphone struggles with the fundamental.
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