About this tool
Tune your guitar, bass, ukulele, violin, viola or cello right in your browser – no app needed. The tuner listens through your device’s microphone, detects the pitch of the note you play and shows how many cents it is sharp or flat. In chromatic mode it recognises any note; for an instrument it compares with the closest string.
The microphone signal is analysed only locally in your browser and is neither recorded nor sent to a server. Besides standard tuning there are Drop D, DADGAD and half a step down for guitar, plus 4- and 5-string bass. You can change the concert pitch (e.g. 442 Hz) and listen to each string as a reference tone. To convert between frequencies and notes, use the Note Frequency Converter converter.
How it works
- Choose your instrument and tuning – or “Chromatic” for any note.
- Click “Start tuner” and allow access to the microphone.
- Pluck a single string and turn the peg until the needle is centred and the note turns green.
Frequently asked questions
Is my recording saved or uploaded?
No. The tuner reads the microphone signal in small chunks directly in the browser, calculates the pitch and discards the data immediately. Nothing is recorded and nothing is sent to no.tools or any other server.
How accurate is the online tuner?
It uses the YIN pitch detection algorithm and is accurate to about one cent for a clear single note; a deviation below 5 cents counts as in tune. It works best in a quiet room, with one plucked string and the device close to the instrument.
Why does it sometimes show the wrong octave or jump?
Right after plucking and while the note decays, overtones are often stronger than the fundamental. Wait a moment after plucking and do not strike several strings at once. In instrument mode the closest string is always shown; very low strings (the low B of a 5-string bass) need a microphone that picks up low frequencies.
Why won’t the microphone start?
Your browser has to allow access – a prompt appears the first time. If you declined it, allow the microphone in the site settings (usually via the lock icon in the address bar). Microphone access only works over a secure HTTPS connection and may be blocked in embedded versions on other websites.