Sing or play any note — see its pitch instantly.
Every voice sits in its own band. Pick soprano, mezzo, alto, tenor, baritone, or bass before you sing. The detector then watches only that octave, so a low male voice is never mis-read as a high female note — the classic octave-confusion problem is solved before it starts.
Most music uses 440 Hz as concert pitch, but orchestras often tune to 442 Hz, and some players prefer 438 Hz or the vintage 432 Hz standard. Set your reference above and every note is measured against the right A — handy when you practice with a piano, a band, or a vintage recording.
A pitch detector is the core tool of PitchTester: point your microphone at any sound and it tells you the note name, the frequency in hertz, and how many cents sharp or flat you are, all in real time. Singers use it to check intonation, guitarists use it as a quick tuner, and producers use it to label a recorded note. A pitch detector turns the question "am I on the right note?" into a number you can act on, with no app to install and no account to open.
The pitch detector is the front door, but it sits inside a small set of tools that share one engine. Need to score your singing in cents? That is the pitch tester. Want to name a note by ear? The note finder. Prefer a live readout while you play? The note detector. Converting a pitch to a frequency? The pitch finder. Tuning a guitar? The tuner. Finding a song's key? The song key finder. Generating a reference tone? The tone generator. Each page uses the same accurate detection, so a note reads the same everywhere — pick the one that matches the words you searched for.
Under every PitchTester tool is one pitch-detection engine built on the YIN algorithm. It analyses short frames of microphone audio, estimates the fundamental frequency with autocorrelation, smooths the result, and converts it to a note name and cents using twelve-tone equal temperament. Because the engine is shared, the pitch detector, the tuner, and the key finder all agree on what a note is — there is no drift between tools. The whole thing runs in your browser through the Web Audio API, so it starts instantly and stays private.
Every PitchTester tool is built so your audio never leaves your device. The microphone signal is analysed locally, the result is drawn on the page, and nothing is uploaded, stored, or sent to a server. That privacy holds on a phone in a rehearsal room, a laptop at home, or a tablet in a lesson — the pitch detector behaves the same everywhere because the work happens on your hardware. No account, no install, no clip of your voice sitting on someone else's server.
The fastest way to make a pitch detector useful is to use it often and briefly. A two-minute check before practice trains your ear faster than a long session once a week, because the feedback stays fresh. Set your voice range so the pitch detector reads the right octave, pick your reference tuning to match the music you play with, and sing a steady note to watch the cents settle. Over time the pitch detector becomes less of a meter and more of a habit — the quiet check that keeps every note honest, whether you are warming up, recording, or simply curious what you just sang into the mic.
Reference table for standard A4=440 Hz tuning
| Note | Frequency | Description |
|---|---|---|
| C2 | 65.41 Hz | Deep bass — cello C string |
| E2 | 82.41 Hz | Lowest guitar string (E) |
| C3 | 130.81 Hz | Bass / baritone vocal range |
| A3 | 220.00 Hz | Below middle — tenor range |
| C4 | 261.63 Hz | Middle C — soprano/alto start |
| E4 | 329.63 Hz | High open guitar E string |
| G4 | 392.00 Hz | Violin open G string |
| A4 | 440.00 Hz | Standard tuning reference (A440) |
| C5 | 523.25 Hz | High C — soprano upper range |
| E5 | 659.25 Hz | Whistle / high vocal range |
| C6 | 1046.50 Hz | Soprano high C (doo-wop) |
A pitch detector uses your microphone to identify the note you sing or play — showing its name, frequency, and how sharp or flat you are in cents.
Yes, 100% free forever — no sign-up, no download. Everything runs in your browser.
Yes, any modern browser on phone, tablet, or desktop, including iOS and Android.
Yes — play a string and it shows the nearest note and whether it is sharp or flat.
No. All audio processing happens locally in your browser. Nothing is ever uploaded.
Select your voice range (soprano to bass) so the detector focuses on the correct octave.
440 Hz standard, 442 Hz orchestral, 438 Hz, and 432 Hz vintage.
A pitch detector is the fastest way to check whether the note you're singing is on key. Singers use it for daily ear training, students practice intonation, and teachers demo intervals in class. Our free online pitch tester works entirely in your browser, so there is nothing to install and no account to create.
Sing into the mic and the detector reads your note name, frequency in Hz, and cents deviation in real time. Because it is a true in-browser pitch detector, your audio never leaves the device — private by design. Select your voice range and reference tuning and the tool filters out octave confusion, making it perfect for voice practice, guitar tuning, and learning any instrument.
PitchTester is a small set of free, browser-based music tools built around one idea: you should be able to check pitch, tune an instrument, name a note, or find a song's key without installing an app, creating an account, or uploading a single byte of audio. Every tool here runs entirely on your device using the Web Audio API — your microphone signal never leaves the browser, so your practice stays private by design.
We focus on doing a few things well instead of bolting on features. The pitch detector and its siblings share one accurate YIN-based engine, so a note read on the tuner matches a note read on the key finder. Whether you are a singer working on intonation, a guitarist tuning between songs, or a producer checking a sample's key, the same fast, private toolkit is one tap away — on phone, tablet, or desktop.
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