OnlineBassTuner

How to Tune a Bass

Six steps, about a minute, for any electric or acoustic bass.

  1. Get ready

    Sit in a quiet spot. Hold your phone or laptop close to the bass, or near the amp speaker if you are plugged in. Choose your tuning on the tuner below and press Start tuner.

Bass tuner

Uses your microphone. Nothing is recorded.

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Microphone is blocked

The tuner can’t hear your bass until you allow the microphone for this site. 1. Open the site settings for this page (steps for your browser below). 2. Set Microphone to Allow, then press Try again.

Chrome on a computer

Click the icon to the left of the web address, set Microphone to Allow, then reload the page.

Microsoft Edge

Click the lock icon to the left of the web address, open Permissions for this site, set Microphone to Allow and reload.

Firefox

Click the crossed-out microphone icon in the address bar, clear the blocked permission, reload and choose Allow when asked.

Safari on a Mac

Open Safari, Settings, Websites, Microphone, and set onlinebasstuner.app to Allow or Ask. Then reload the page.

iPhone or iPad

Tap the page menu (aA) in the address bar, open Website Settings and set Microphone to Allow or Ask. Then reload the page.

Chrome on Android

Tap the icon to the left of the web address, open Permissions and turn on Microphone. Then reload the page.

Or tune by ear: tap a string button below to hear its note, or use the reference tones ↓.

Reference pitch A4 = 440 Hz

  1. Play the thickest string open

    Pluck it once at normal strength and let it ring. Mute the other strings with your fretting hand.

  2. Read the needle

    Left of centre (flat) means tighten the string, right of centre (sharp) means loosen it. The cents number shows how far off you are; within 5 cents counts as in tune.

  3. Turn the peg slowly

    Small turns make big changes on a bass. If you overshoot, go below the note and come up again.

  4. Repeat for every string

    Work from the thickest to the thinnest string. The string buttons get a tick when a string has been in tune for a moment.

  5. Check again

    Play through all strings once more. Tightening one string pulls slightly on the neck, so a quick second pass is normal.

To tune a bass, play one open string, read the tuner and turn that string’s peg until the note is in the centre. Tighten if the note is flat, loosen if it is sharp. Start with the thickest string, tune each string in turn, then check them all once more.

Tuning without a tuner

If one string is right, you can tune the rest from it. On a standard bass, the 5th fret of each string matches the next open string (E 5th fret = A, A 5th fret = D, D 5th fret = G). You can also compare harmonics: the 5th-fret harmonic on one string and the 7th-fret harmonic on the next string give nearly the same note. Harmonic tuning is about 2 cents off from equal temperament, which is close enough for most playing but not exact.

Intonation is a different thing

If open strings are in tune but notes high on the neck sound sharp or flat, the bass needs an intonation adjustment at the bridge. Compare the 12th-fret note with the 12th-fret harmonic; if they differ, the saddle position needs to change.

Other tunings: 5-string, Drop D and lower, or tune by ear with the reference tones.

Questions and answers

How often should I tune my bass?

Every time you play. Temperature, humidity and playing all move the strings a little. New strings stretch and need retuning several times during the first days.

Should I tune up or down to the note?

Up. If the string is sharp, go a little below the note and then come up to it. This takes up slack in the tuning machine, so the string stays in tune longer.

Why does the note go sharp right after I pluck?

A hard pluck stretches the string and raises the pitch for a moment. Watch the needle after the first instant, when the note has settled, and pluck at your normal playing strength.

Is a clip-on tuner better than a microphone tuner?

A clip-on tuner senses the vibration of the headstock, so it ignores room noise. A microphone tuner like this one needs no extra device and works well in a quiet room, especially with the microphone close to the bass or amp.

More bass tools

Last updated October 23, 2026.