Tune any instrument with this free online tuner. Allow your microphone, play a note, and it shows the pitch and how many cents you’re sharp or flat — a chromatic tuner for guitar, bass, ukulele, violin, voice and more. Nothing is recorded or uploaded.
Online Tuner
A free chromatic tuner for guitar, bass, ukulele, violin, voice — any instrument. Allow your microphone, play a note, and it shows the pitch and how many cents you are sharp or flat. Nothing is recorded or uploaded.
Turn the volume down on other sound and play a single, clear note. The needle centres and turns green when you’re in tune (within 5 cents). Everything runs on your device — the microphone audio is analysed live and never recorded or sent anywhere. Standard tuning reference is A4 = 440 Hz.
How to tune an instrument
- Start the tuner and allow microphone access when your browser asks.
- Play one clear note — a single string or sung note works best.
- Watch the needle — it shows the detected note and how far off you are. Tune until the needle centres and turns green (within 5 cents).
What you can tune
- Guitar — standard tuning is E A D G B E. The low E is E2 (about 82 Hz).
- Bass — E A D G, an octave below the guitar’s bottom four strings.
- Ukulele — standard is G C E A.
- Violin, cello & more — it’s chromatic, so it reads any note.
- Voice — check whether you’re hitting a note in tune.
Accurate and private
The tuner analyses your microphone live on your device and shows the pitch to within a cent. The audio is never recorded or sent anywhere — it’s processed in your browser and discarded frame by frame. The reference is standard concert pitch, A4 = 440 Hz. Want a reference tone to tune to instead? Use the Tone Generator, and to find a song’s key, try the BPM & Key Finder.
Frequently asked questions
Does it work for guitar and bass?
Yes — it’s a chromatic tuner, so it reads every note including the low strings on guitar and bass. Play one string at a time for the clearest reading.
What are cents?
Cents measure how far a note is from perfectly in tune: 100 cents make one semitone. The tuner shows the needle centred and green when you’re within 5 cents.
Does it record or upload my audio?
No. The microphone audio is analysed live in your browser and never recorded or sent anywhere.
Why does it need microphone access?
The tuner listens to your instrument through the microphone to detect the pitch. Access is only used while the tuner is running, and you can stop it at any time.
Does it work on mobile?
Yes — allow microphone access in your mobile browser and play a note near the device.
Is it really free?
Completely — no signup and no limits.