The short answer: Free, and it runs on the phone's own microphone — no account, and no clip-on tuner to buy. Play a string, and the guitar tuner listens through the microphone, names the note it hears and shows how many cents sharp or flat it is. Pick an instrument and one of dozens of named tunings — standard, drop, open and more — and it automatically targets the nearest string, or tap a peg on the on-screen headstock to hear the reference note first. Everything runs on the device; nothing is uploaded. It is a guitar tuner online, with no clip-on hardware to lose.
Last updated: August 2026
Getting in tune by ear works, but it's slower than it needs to be. The Tuner turns the microphone into a pitch detector: play a note, and it names it and shows exactly how far off it is, in cents.
Play any string and the tuner listens through the microphone, detects the pitch, and shows the nearest note along with how many cents sharp or flat you are. It automatically targets the nearest string of whichever tuning is selected, so there's no need to tell it which string you're on.
The tuner covers 12 instruments across 6 families: 6, 7 and 8-string guitar; 4 and 5-string bass; ukulele; 4 and 5-string banjo; mandolin; violin; viola; and cello. Between them there are 80 named tunings — 6-string guitar alone has 22, covering standard, drop and a range of open tunings.
Not sure what a string is supposed to sound like before you start? Tap the corresponding peg on the on-screen headstock and the tuner plays that string's reference note.
The microphone signal is processed on the device to detect pitch; it is not uploaded anywhere, and the page states this directly. The instrument and tuning you last selected are remembered in the browser, so returning to the page picks up where you left off — no account is needed for any of it.
Can I tune a piano with it? No. The tuner covers guitar, bass, ukulele, banjo, mandolin and the orchestral strings (violin, viola, cello) — there's no piano tuning.
Is my microphone audio sent anywhere? No. Pitch detection runs on the device itself; the audio is not uploaded.
Do I need an account to use the tuner? No. Instrument and tuning choices are remembered in the browser automatically, and no sign-in is required to tune.