Free Guitar Tuner With Mic (Online, No App)
Tap Start, allow the mic, then play one string at a time. Tune UP to the pitch (from slightly flat) and mute the other strings.
Tap a string to tune to it (or leave on Auto). Tap the speaker button to hear its reference tone by ear.
Privacy: Mic audio is processed locally in your browser to detect pitch. It is never recorded, uploaded, or stored. The mic stream stops when you press Stop or leave this page. Mic access requires HTTPS (this site is HTTPS). If the mic is denied, use the reference tones: play a string tone, then match your string to it by ear.
How to tune
- Pick your preset (Standard for most lessons).
- Play one open string at a time, letting it ring; mute the others with your free hand.
- If the readout says FLAT, tighten the peg a little; if SHARP, loosen - then tune back UP to pitch from slightly flat for stability.
- Green / IN TUNE means within about 5 cents. Recheck all six strings once - changing one can shift the others slightly.
String order, low to high: E - A - D - G - B - E (thickest to thinnest). No mic handy? Tune by ear with the 5th-fret method. Tuning a bass? Use the bass tuner (E A D G, plus low B for 5-string). Then head to the chord library, metronome or practice timer.
Alternate tunings
Pick the tuning in the preset menu, then tune each string to its new target. Frequencies are standard equal-temperament pitches at A = 440 Hz.
| Tuning | Strings, low to high | Used for |
|---|---|---|
| Standard | E2 A2 D3 G3 B3 E4 | Almost everything; all our lessons |
| Drop D | D2 A2 D3 G3 B3 E4 | Heavier rock riffs; one-finger power chords |
| Half-step down (Eb) | Eb2 Ab2 Db3 Gb3 Bb3 Eb4 | Playing along with recordings tuned down; slightly easier bends |
| Open G | D2 G2 D3 G3 B3 D4 | Slide and blues; strum open for a G chord |
| Open D | D2 A2 D3 F#3 A3 D4 | Slide, folk; strum open for a D chord |
| DADGAD | D2 A2 D3 G3 A3 D4 | Celtic and folk fingerstyle |
| Bass, 4-string | E1 A1 D2 G2 | Standard bass tuning; see the bass tuner |
| Bass, 5-string | B0 E1 A1 D2 G2 | Five-string bass with a low B |
- Tuning down (Drop D, Eb, open tunings that lower strings): loosen past the target, then tune back up to it.
- Tuning up (Open D's F#, raising strings): go slowly - over-tightening is how strings snap. Never tune a string far above its standard pitch.
- Switching tunings often can upset the neck relief a little; give the guitar a few minutes and re-check.
Troubleshooting
| Problem | Try this |
|---|---|
| Needle jumps around | Mute the other strings with your fretting hand; pluck firmly once and let it ring; move closer to the mic (about 15-30 cm / 6-12 in) |
| Shows the wrong string or an octave off | Tap "Tune to this" on the string you're tuning so the tuner stops guessing |
| Nothing happens after Start | Allow the microphone (lock or mic icon in the address bar), then press Start again; check that no other app is using the mic |
| Mic level bar stays empty | Your device may be using a different mic, such as a headset - select the right input in system settings |
| Noisy room | Turn off fans or TV; or use a clip-on tuner, which reads vibration instead of sound |
| Low E reads unsteadily | Pluck a little softer with the flesh of the thumb; low strings have strong overtones that can confuse any mic tuner |
| No mic at all | Use the Hear tone buttons and match each string by ear |
Why strings go out of tune
New strings stretch for the first few days, temperature and humidity changes move the neck, and tuning down to pitch leaves slack at the tuner post. Tune up to each note, re-check all six after one pass, and see guitar won't stay in tune if it keeps drifting.
Safety notes
- Tune up slowly; an over-tightened string can snap - keep your face away from the headstock while raising pitch.
- Keep reference tones at a comfortable volume, especially in headphones.
FAQ
How accurate is a microphone tuner?
In a quiet room it is close enough for everyday tuning; it shows IN TUNE within about 5 cents. A clip-on tuner copes better with background noise.
Is my audio recorded?
No. The sound is analysed in your browser and never uploaded or stored.
Why does it say FLAT when it sounds right?
Small differences of a few cents are hard to hear. Trust the needle, then check a chord: if G and C both sound good, you're there.
Which tuning should a beginner use?
Standard (E A D G B E). Every chord diagram on this site assumes it.
How to tune a guitar with your mic
- Tap Start and allow microphone access when the browser asks.
- Hold the phone or laptop about a foot from the soundhole (acoustic) or the amp speaker (electric).
- Pick one string at a time and let it ring. Mute the others with your fretting hand.
- Turn the tuning peg until the needle sits at 0 cents. If you're sharp, go below the note and come back up to it, so the string holds its tuning.
- Go low E to high E, then check every string once more. Tuning one string changes the neck tension a little.
If the mic tuner won't read
- Check the browser's site settings and make sure the mic is allowed. Safari and Chrome both need HTTPS, which this page uses.
- Turn off fans, TV or music. Background noise hides the low strings.
- Pick a bit harder, and wait half a second after the attack before you read the needle.
- Low E reading wrong? Laptop mics pick up the overtones. Move closer or play the 12th-fret harmonic.
FAQ
Can I tune my guitar with my phone's microphone?
Yes. Open this page in your phone's browser, tap Start, allow the mic, and play one string at a time. No app needed.
Is this guitar tuner with mic free?
Yes. It runs in your browser, with no signup or download, and the audio never leaves your device.
Why does the tuner jump around?
Usually other strings ringing or background noise. Mute the other strings, get closer to the mic and let the note settle.
What are the standard tuning notes?
E A D G B E, low to high (E2 82.4 Hz, A2 110 Hz, D3 146.8 Hz, G3 196 Hz, B3 246.9 Hz, E4 329.6 Hz).
Does it work for bass or ukulele?
Yes for bass: pick Bass, 4-string (E1 A1 D2 G2) or Bass, 5-string (B0 E1 A1 D2 G2) in the preset menu, or open the bass tuner page. There is no ukulele preset yet; the needle still reads any note, so watch the note name and cents gauge.
Sources checked
- String frequencies: standard 12-tone equal temperament with A4 = 440 Hz (computed: f = 440 x 2^((n-69)/12)).
- Tuning uses are general descriptions in our own words.
Not hands-on testing: troubleshooting steps are general guidance, not product tests.
Related step-by-step guides
- Best guitar tuner app - free app options compared, and how to tune with a phone.