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Toolvica

Tuner

Tune guitar, bass, ukulele, violin and more with your microphone. Live note, frequency and cents needle with reference pitches.

Mic off

—

— Hz · — cents

-50 ♭ flatMic off+50 ♯ sharp

440

What this tuner offers

Tune with your microphone in Chromatic, Guitar EADGBE, Bass EADG, Ukulele GCEA, Violin GDAE, Viola CGDA or Cello CGDA mode. The big note with octave, exact frequency in Hz and plus or minus cents update live many times per second, with needle, status pill and closest-string label.

How to read it. The needle spans minus 50 to plus 50 cents with red, amber and green zones. Center with green pill means in tune within 5 cents. Needle left means flat, tighten the string. Needle right means sharp, loosen it. Always tune up from below and let each note ring before judging.

How to use the sound. Tap any string chip or the Hear target button to play the correct reference pitch, then play your string together with it. Out-of-tune notes beat or pulse against each other. The pulsing slows as you converge and stops when matched, so you can tune by ear as well as by eye.

  • Chromatic detection across all twelve notes for any instrument or voice
  • Seven modes with tap-to-hear string chips for each instrument
  • Hear target button plays the detected note's ideal pitch
  • A4 reference 435 to 445 Hz for orchestras and old pianos
  • Green in-tune indicator at plus or minus 5 cents, amber to 15
  • Mic off idle state, Listening prompt, and private live analysis with nothing recorded

How to use

  1. Click Start mic, allow microphone access, and play one string or note at a time in a quiet room.
  2. Read the big note with octave, exact Hz and plus or minus cents on the needle. Green pill and needle at center within 5 cents means in tune, left is flat so tighten, right is sharp so loosen.
  3. Pick Chromatic for any instrument, or Guitar, Bass, Ukulele, Violin, Viola or Cello to see the closest string chip. Tap any chip or Hear target to play the correct pitch and match it by ear.
  4. Adjust A4 from 435 to 445 Hz if your group tunes off 440. Tune each string up from below, let notes ring, then click Stop. Mic off means the microphone is not listening.

What is a tuner?

Every note has a target frequency. A4 at 440 Hz means the A above middle C vibrates 440 times per second. Other notes follow twelve-tone equal temperament.

The tuner measures your pitch many times per second and shows cents, which are hundredths of a semitone. Zero cents is perfect, plus means sharp, minus means flat.

At A4 440 Hz the open guitar low E rings near 82 Hz and high E near 330 Hz. Watch the needle settle after the pluck attack, then turn the peg until the pill turns green within 5 cents and the beating against the reference pitch stops.

Features

Live pitch detection

Autocorrelation on your mic signal shows note, octave, Hz and cents with a smooth needle.

Instrument modes

Chromatic for any instrument, plus Guitar, Bass, Ukulele, Violin, Viola and Cello string helpers with tap-to-hear reference pitches.

Adjustable reference

Set A4 from 435 to 445 Hz to match orchestras, old pianos or historical pitch.

Private by design

Audio is analyzed live in your browser. Nothing is recorded or uploaded.

Tips

Play one note

Mute other strings and let the note ring. Chords confuse any tuner.

Tune up

Tune from below the pitch upward so string tension holds the tuning.

Quiet room

Background noise and fans pull the reading. Get close to the mic.

FAQ

Which instruments can I tune?
Any monophonic source: guitar EADGBE, bass EADG, ukulele GCEA, violin GDAE, viola and cello CGDA, plus voice, brass and woodwinds in Chromatic mode. Play one string or note at a time, because chords produce competing pitches that confuse autocorrelation.
Why does the needle jump when I pluck?
Pick attack reads sharp for a fraction of a second before the string settles. Ignore the first flicker, let the note ring, and tune to the stable reading. If it never settles, move closer to the mic, mute other strings, and cut background noise.
What is A4 reference pitch?
The anchor all notes derive from via twelve-tone equal temperament. 440 Hz is the ISO standard, many orchestras use 442 to 443, baroque ensembles use 415. Set the slider to your group and every detected note shifts accordingly.
Is my microphone audio recorded or uploaded?
No. getUserMedia audio flows into an AnalyserNode and is discarded frame by frame. Nothing is stored, no network calls are made, and stopping the mic closes the stream and audio context immediately.
What do cents mean and how close is in tune?
Cents are hundredths of a semitone, so 100 cents is the next note. Zero is perfect, minus is flat and plus is sharp. Within plus or minus 5 cents shows green In tune and is inaudible alone, 5 to 15 amber is fine for practice, beyond 15 you will clash with other instruments.
How do string chips and Hear target work?
Pick your instrument mode to see its string chips, for example six for guitar. The closest-string label follows your pitch live. Tap any chip or Hear target to play the ideal sine pitch, then play your string against it: the beating pulsation slows as you converge and stops when matched, so you can tune by ear as well as needle.

References

1. Web Audio API — MDN. developer.mozilla.org/Web/API/Web_Audio_API

2. Twelve-tone equal temperament with A4 reference pitch.

For practice and education. Timing accuracy depends on device performance and browser audio scheduling. For critical recording, compare with a hardware metronome.