Is this online tuner free?

Yes. It is free, has no ads and needs no account. It runs in your browser using the Web Audio API.

Is my microphone audio recorded or uploaded?

No. The sound is analysed live inside this browser tab to find the pitch. Nothing is recorded, stored or sent to a server.

What are standard tunings for guitar, ukulele and violin?

Guitar: E2 A2 D3 G3 B3 E4. Ukulele: G4 C4 E4 A4. Violin: G3 D4 A4 E5. Bass: E1 A1 D2 G2. Cello: C2 G2 D3 A3.

Can I change A4 from 440 Hz?

Yes. Set the reference anywhere from 415 to 466 Hz, for example 442 Hz for many orchestras or 432 Hz if you prefer it.

On a clean signal the pitch detector reads within about 1 cent. Background noise and a phone's built-in mic make it less steady, so play one string at a time close to the mic.

Is there an app version?

Yes. Maestro for iPhone and Android has the same tuner offline, plus a metronome and practice log. The tuner and basic metronome are free; Pro is a one-time purchase, never a subscription.

Free online tuner

Tap Start, allow the microphone, and play one string. The needle shows how many cents sharp or flat you are, and turns green when you are in tune. Audio is analysed in this tab and never uploaded.

InstrumentA4 reference (Hz)

–

Tap Start and allow the microphone

-50

-25

+25

+50

Tap a string to hear its reference note

Audio is analysed in this tab only. Nothing is recorded or uploaded.

The same tuner in the Maestro app: works offline, with a haptic tick when you hit the note.

Tuner and basic metronome free forever, no ads, no nag pop-ups. Pro is $4.99 once: pay once, no subscription.

Download on theApp Store Get it onGoogle Play

How to tune with this online tuner

Pick your instrument (or Chromatic for anything else).
Tap Start and allow microphone access when the browser asks.
Play one open string and let it ring.
If the needle is left of centre the string is flat: tighten it. Right of centre is sharp: loosen it.
Stop when the note turns green (within 5 cents), then move to the next string.

Frequently asked questions

Is this online tuner free?: Yes. It is free, has no ads and needs no account. It runs in your browser using the Web Audio API.
Is my microphone audio recorded or uploaded?: No. The sound is analysed live inside this browser tab to find the pitch. Nothing is recorded, stored or sent to a server.
What are standard tunings for guitar, ukulele and violin?: Guitar: E2 A2 D3 G3 B3 E4. Ukulele: G4 C4 E4 A4. Violin: G3 D4 A4 E5. Bass: E1 A1 D2 G2. Cello: C2 G2 D3 A3.
Can I change A4 from 440 Hz?: Yes. Set the reference anywhere from 415 to 466 Hz, for example 442 Hz for many orchestras or 432 Hz if you prefer it.
How accurate is it?: On a clean signal the pitch detector reads within about 1 cent. Background noise and a phone's built-in mic make it less steady, so play one string at a time close to the mic.
Is there an app version?: Yes. Maestro for iPhone and Android has the same tuner offline, plus a metronome and practice log. The tuner and basic metronome are free; Pro is a one-time purchase, never a subscription.

Get Maestro: tuner, metronome and practice log in one app.

Download on theApp Store Get it onGoogle Play