About Harmonu
Harmonu is a set of free online tuners for guitar, ukulele, bass guitar, banjo, violin, viola and cello, plus a chromatic tuner for any other instrument. Open a page, allow the microphone, play a note, and the meter shows how far you are from the right pitch. There is nothing to install and no account to create.
Why Harmonu exists
Harmonu was founded on a simple principle: tuning your musical instrument should be free, fast, and accessible directly from your browser, with no subscription barriers or account requirements.
How it works
- Tune with your microphone. Pluck a string and Harmonu detects the pitch of the sound in real time, finds the closest string of your instrument, and shows on the meter whether the string is too low, too high, or in tune.
- Tune by ear. Tap a peg (or a note on the chromatic wheel) to hear a reference tone, then turn the peg until your string matches it.
- Choose your tuning. Each tuner offers the common tunings for its instrument, such as standard tuning for the ukulele and guitar.
Privacy by design
Our tuners use the Web Audio API built into your browser to analyse sound frequencies directly on your device. Audio from your microphone is never stored, recorded, or transmitted to any server. Read more in our Privacy Policy.
For the best results
- Tune in a quiet room, away from fans, music and TV.
- Play one string at a time and let it ring.
- Hold your device close to the instrument.
- Tune up to the note: if you are too high, go a little below it first, then tighten slowly.
The tuners use standard concert pitch, with A4 = 440 Hz.
Our tuners
- Chromatic Tuner
- Guitar Tuner
- Ukulele Tuner
- Violin Tuner
- Viola Tuner
- Cello Tuner
- Bass Guitar Tuner
- Banjo Tuner
Get in touch
Feedback, a question, or a tuning you would like to see? We would love to hear from you on our contact page.