A free online tuner that uses your microphone: guitar, bass, ukulele, violin, or chromatic, with a cents meter and reference tones. No app.
The tuner listens through your microphone and shows the note you're playing, its frequency, and how far off it is in cents, with a needle that centres when the string is in tune. Choose guitar, bass, ukulele, or violin to lock the display to that instrument's open strings, or chromatic mode to tune anything to the nearest semitone. Tap a string to hear its reference note, and change the A4 reference from the standard 440 Hz if you're matching another instrument or a recording.
Play one string at a time and let it ring; a quiet room and a phone or laptop held close give the steadiest reading. The pitch is worked out on your device from the live signal — nothing is recorded, stored, or uploaded, and the microphone is released when you stop or leave the page. What semitones and cents are explains the meter, and concert pitch and A440 covers the reference setting.
It reads the live signal from your microphone and measures how often the waveform repeats, which gives the pitch of the note. It then shows the nearest note and the difference in cents, where 100 cents is one semitone. A reading within about 5 cents of zero is in tune for practical purposes.
Yes. There are presets for guitar, bass, ukulele, and violin in standard tuning, each showing its open strings, and a chromatic mode that follows any note. Chromatic mode is the one to use for alternate tunings, other string instruments, or checking a wind instrument or voice.
Usually because more than one string is sounding, the room is noisy, or the note has faded. Mute the other strings, pluck one string firmly, and let it ring close to the microphone. Low bass notes are the hardest for phone and laptop microphones to pick up, so move closer for those.
No. The microphone signal is analysed on your device as it arrives and then discarded. Nothing is recorded, stored, or uploaded, and the microphone is released as soon as you stop the tuner or leave the page.