Bass Tuner Online
Tune all four strings to E A D G with nothing but your microphone — a pitch engine windowed for the bass register hears even the low E, names the string, and says which way to turn. Free, nothing recorded.
Tap a peg to hear its note and start tuning — the browser will ask for mic access once. Sound is analyzed on your device, never uploaded.
How to Tune a Bass Guitar Online
E A D G from the bottom up — firm plucks, four green checks.
Give the Mic Access
Press Tune my bass and allow the microphone when the browser asks. The analysis never leaves your device.
Pluck Firmly, Up Close
Bass notes are low, so help the mic: play one string with a solid pluck near the pickup and keep the instrument close to your device.
Follow the Arrow to Green
The tuner names the string and says tune up or tune down. Center the needle, hold it, collect the check — then on to the next string.
A Tuner That Can Actually Hear a Bass
Low-register pitch tracking, plain directions, and a check per string.
Built for the Low Register
The pitch engine is windowed for 30–150 Hz and reads a bass through its overtones — so even the 41 Hz open E resolves instead of vanishing into rumble.
Auto-Detects E, A, D, or G
Pluck a string and the tuner figures out which of the four you meant. A badly detuned string confusing it? Tap the right peg to lock the target.
Direction, Not Interpretation
The readout says tune up or tune down in words, with the cents needle as proof. Within 5 cents of target, it goes green — done.
Reference Tones for Each String
Play the target pitch for any string out loud. Handy for tuning by ear, and for checking a 5-string's low B against the tuned E by harmonics.
Analysis, Never Recording
Every frame of mic input is measured on your device and immediately thrown away. No audio is kept, stored, or uploaded — ever.
Phone-Friendly
Works in the browser on iOS and Android as well as desktop — tune at rehearsal, in the studio hallway, or backstage before the set.
Your Signal Never Leaves the Room
The tuner measures each incoming frame of microphone audio on your own device and discards it on the spot. Nothing is recorded or uploaded, and Stop kills the mic immediately.
No Recording
Frames are analyzed and discarded
No Upload
The analysis runs in your browser
You're in Control
Stop ends mic access instantly
Whenever the Low End Drifts
Nobody notices a bass until it’s out of tune — then everybody does.
Electric & Acoustic Bass
Unplugged close to the mic, or through a small practice amp — both track fine
Before Tracking
A flat E string ruins every note of a recorded bassline — check first
Rhythm Section Lock-In
Bass and guitar referenced to the same A 440 is what makes a band sound tight
New Bassists
Plain up/down directions — no guessing which way the machine head goes
No Pedal Tuner Handy
Left the tuner pedal on the board at the venue? Any browser fills in
Harmonic Tuning Practice
Tune by harmonics first, then let the needle audit your ear
E A D G, One Octave Down
A standard 4-string bass tunes to E1 A1 D2 G2 — the same four note names as a guitar’s lowest strings, dropped exactly one octave. The open E vibrates at just 41.2 Hz, a pitch closer to feeling than hearing, and the whole instrument tops out around 98 Hz on the open G. Everything is referenced to A4 at 440 Hz, so a bass tuned here sits perfectly against any other instrument tuned to concert pitch. This page listens for those four low notes, identifies the string, and walks it to center in cents.
Why 41 Hz is the hard part — and how the tuner handles it
Phone speakers barely reproduce a low E, and phone microphones don’t love capturing one either: at that depth, most of the audible energy lives in the string’s overtones rather than the fundamental. The engine behind this tuner is windowed specifically for the bass register — a long analysis frame and a 30–150 Hz search range — so it reconstructs the true pitch from those overtones instead of getting lost in room rumble. Your half of the bargain is a strong signal: pluck firmly, and get the instrument close to the mic.
Technique for a clean low-string reading
One string at a time, always. On the E and A strings, pluck near the pickup or over the 12th fret with a bit more force than usual — both spots emphasize the overtones the tuner reads best — and let the note sustain rather than muting it early. Playing an electric bass unplugged works at close range in a quiet room; if the needle keeps dropping out, run the bass through a small practice amp placed next to your device and it will track every pluck. When a string is far from pitch, tap its peg to lock the target so auto-detect can’t wander to a neighbor.
Five strings? Handle the B by harmonics
A 5-string’s low B sits at roughly 30.9 Hz — below what any microphone tuner can read honestly. The reliable route: tune E A D G here first, then match harmonics by ear. Touch the E string above the 7th fret and the B string above the 5th; the two chimes should be the same pitch, and the slow “beating” you hear between them disappears exactly when the B is right. It’s the same skill bassists have used for decades, with the tuner guaranteeing your anchor string is true. To dig into pitch and frequency further, the pitch detector shows the exact Hz of anything the mic hears.
The rest of the band
Same engine, different registers: the guitar tuner covers your six-string bandmates, the cello tuner handles the other big low-register string instrument, and the ukulele and violin tuners take the high end. When the low end is locked and you’re ready to lay down a take, the online audio editor records and cleans it up in the same browser.
Low End Locked? Track It
The full Notevibes Online Audio Editor records your bassline, cleans up room noise, detects key and tempo, and exports to MP3 or WAV — all in your browser.
Free to try · No credit card required
Related Audio Tools
More free AI audio tools from Notevibes — same engine, no sign-up.
Guitar Tuner
Tune all six strings with your mic — auto string detection.
Ukulele Tuner
Tune G C E A with your mic, string by string.
Cello Tuner
Tune C G D A with your mic — fifths made easy.
Pitch Detector
Read the live pitch of any sound — Hz, note, and cents.
BPM Detector
Find the BPM, key, and Camelot code of any song.
Online Audio Editor
Multi-track browser editor with every tool built in.
Bass Tuner FAQ
How do I tune my bass with this online tuner?
Press the button, allow microphone access, and pluck one string firmly. The tuner identifies the string, measures the offset in cents, and tells you whether to tune up or down. Turn the machine head slowly until the needle centers and turns green, hold briefly, and that string gets a check. Four checks and the bass is set.
What tuning does it use?
Standard 4-string tuning — E1 A1 D2 G2, referenced to A4 = 440 Hz. That's exactly one octave below the four lowest strings of a guitar in standard tuning, which is why bass and guitar parts share the same note names.
Why won't it pick up my low E string?
The open E fundamental sits at 41.2 Hz — right at the bottom edge of what phone mics and laptop mics capture well. Pluck firmly (near the pickup or over the 12th fret), get the bass close to the mic, and let the note ring. The tuner reads the string's overtones, so a strong, clean pluck is what makes it lock on.
Can I tune an electric bass without an amp?
Usually, yes. An unplugged electric bass is quiet but not silent — hold it close to the mic in a quiet room and pluck firmly. If readings stay patchy, a small practice amp at low volume placed near your device makes every string easy to track.
What about the low B on a 5-string bass?
B0 at about 30.9 Hz sits below what a microphone tuner can reliably read. Tune the E A D G strings here first, then set the B by ear with harmonics: the 7th-fret harmonic on the E string and the 5th-fret harmonic on the B string should ring at the same pitch — adjust the B until the beating between them disappears.
Is anything recorded or uploaded?
No. The signal is analyzed on your own device in real time and discarded frame by frame — nothing is recorded, stored, or sent to any server, and the mic shuts off the moment you press Stop.
Is it free?
Completely free — no account, no app, no limits. It runs entirely in your browser and only asks for microphone permission, which you can revoke whenever you like.