This free bass guitar tuner shows an interactive 4-in-line headstock — tap a peg to target that string, or let Auto mode detect it for you. No download, no app.
RUNS ENTIRELY IN YOUR BROWSER · YOUR AUDIO IS NEVER RECORDED OR SENT ANYWHERE
Last updated: · Reviewed for accuracy against current browser APIs
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Click "Start Tuning" and allow microphone access to begin.
Start with the thickest E string, closest to you when playing, then work toward the thinnest.
Watch the meter.
Turn the tuning peg slowly — left means flat (tighten), right means sharp (loosen).
Center the needle.
The peg on the headstock turns green once that string is within a few cents of target.
Repeat for all 4 strings.
Then double-check all four again, since tuning one string can slightly pull the others.
How this tuner detects pitch
When you pluck a string, this tool analyzes the sound through your microphone using an autocorrelation algorithm — it compares the waveform against slightly delayed copies of itself to find the point where they line up most closely, and that lag reveals the exact frequency you're playing. This runs entirely in your browser via the Web Audio API; your microphone audio is never recorded, uploaded, or sent anywhere, and it disappears the instant you close the tab.
A brief history of the bass guitar
Next to the acoustic guitar's centuries of history, the electric bass guitar is a genuinely young instrument. It emerged in the USA in the 1930s, when Paul Tutmarc built what was essentially a horizontal, fretted, electric version of the upright double bass — the instrument that had carried basslines in popular music up to that point, but which was large, awkward to amplify, and difficult to transport.
The idea didn't take off commercially until the 1950s, when Fender began mass-producing what became the modern electric bass. Far easier to carry and amplify than an upright bass, it spread quickly among gigging musicians and went on to shape the low end of funk, reggae, rock, pop, and jazz for the rest of the 20th century and beyond.
Standard bass guitar tuning
Standard 4-string tuning, from the thickest string to the thinnest:
String
Note
Frequency
4th (thickest)
E1
41.20 Hz
3rd
A1
55.00 Hz
2nd
D2
73.42 Hz
1st (thinnest)
G2
98.00 Hz
If you play guitar too, this pattern will look familiar — it's the exact same note letters as a guitar's four lowest strings (E A D G), just a full octave lower on the bass.
Is playing bass the same as playing guitar?
The note overlap makes some shapes feel familiar to guitarists picking up a bass for the first time — our Guitar Tuner covers the standard 6-string side of that comparison — but the two instruments are generally played quite differently in practice. Bassists tend to emphasize strong, consistent rhythmic patterns rather than strumming or fingerpicking freely, and within a band the bassist usually locks in tightly with the drummer to build the rhythmic foundation everyone else plays on top of, while the guitarist has more room to focus on melody and interact with other instruments. It's a genuinely distinct role — the bass brings its own particular blend of rhythm and groove that a huge number of well-known basslines across funk, rock, and pop have built entire songs around.
How often should you tune your bass?
Bass guitars generally hold their tuning longer than 6-string guitars, thanks to thicker strings under higher tension, but regular checking is still worth the habit. A reasonable rule of thumb: check your tuning every time you sit down to play, and again if you've been playing continuously for 30 to 60 minutes. If you're performing live, recheck every two or three songs — a quick glance at your set list as a reminder is enough.
How well a bass holds its tuning also depends on things beyond just playing time: how well it's strung, the room's temperature and humidity, and whether it's kept in a case or left out. Wood and strings both respond to environmental swings — a room that stays reasonably stable, roughly 66–77°F (19–25°C) with 40–50% humidity, will keep an instrument in tune noticeably longer than one with wide swings in either direction.
Getting a stable, accurate tuning
Tune up to pitch, not down. If a string reads sharp, loosen it slightly past the target first, then tighten back up to it — tuning that ends on an upward turn holds more reliably than one that ends by loosening.
Turn slowly. Quick, large turns are easy to overshoot, and can occasionally stress a string more than necessary.
Let the string ring cleanly. Avoid muting it or plucking too aggressively while checking pitch — a clean, sustained note gives the tuner far more to work with.
Reduce background noise. A quieter room makes a bigger difference to accuracy than almost anything else.
Why the low strings take a bit longer to lock in
If the tuner feels a touch slower to settle on your low E than it does on your other strings, that's expected rather than a fault. Low frequencies complete far fewer full wave cycles per second than higher ones, so any pitch-detection method — this tool included — genuinely needs to listen to a slightly longer stretch of audio to identify a low note with confidence. Giving the string a clean, sustained pluck rather than a short, muted one gives the detector the fullest possible signal to work with, which is exactly where accuracy matters most on the lowest string.
Frequently asked questions
How do I tune my bass guitar with this tool?
Click Start Tuning, allow microphone access, then pluck a string starting with the lowest E. The closest peg on the headstock highlights automatically, and the needle shows sharp or flat until the peg turns green.
What is standard bass guitar tuning?
Standard 4-string bass tuning, from thickest to thinnest, is E1, A1, D2, G2 — the same note letters as a guitar's four lowest strings, but a full octave lower.
Is a bass tuned the same as a guitar?
The note names match a guitar's four lowest strings exactly, but a bass sits a full octave lower. The instruments are typically played quite differently despite that overlap.
How often should I tune my bass?
Check it every time you sit down to play, and again after 30–60 minutes of continuous playing. Live performers typically recheck every two to three songs.
Should I tune up or down to reach pitch?
Tune up to pitch for the most stable result. If a string is sharp, loosen it slightly past the target first, then tighten back up to it.
What is Drop D bass tuning?
Drop D on bass lowers only the thickest string from E1 to D1, the same concept as Drop D on a 6-string guitar, giving easier access to low power-chord-style root notes.
Does temperature or humidity really affect bass tuning?
Yes. Wood and strings both respond to temperature and humidity changes, so a bass kept somewhere with swinging conditions will drift out of tune more often than one kept in a stable environment.
Can I use this for a 5-string bass or an alternate tuning?
This tool covers standard 4-string tuning and Drop D. For a 5-string's low B, alternate tunings, or anything else outside this list, our Chromatic Tuner listens for all 12 notes rather than a fixed set of strings.
Is my audio recorded or sent anywhere?
No. All detection happens locally in your browser using the Web Audio API. Nothing is uploaded, recorded, or stored.
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Guitar Tuner — standard 6-string tuning with an interactive headstock
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