--- title: "Pitch Detector Online - Note and Frequency | CanDoYa" description: "Use this online pitch detector to identify a note, frequency and cents offset from your voice or instrument. Live audio stays on your device." url: https://candoya.com/tools/pitch-detector/ locale: en type: browser-tool --- # Free Online Pitch Detector Category: Social & Creator ## What is an online pitch detector? An online pitch detector listens to one clear voice or instrument tone and estimates its fundamental frequency. It shows the nearest musical note, octave, hertz value, and cents sharp or flat in real time. The live microphone signal is analyzed in your browser and is never recorded or uploaded. The detector uses normalized autocorrelation to find a repeating period in each short microphone sample, then maps that frequency to the nearest note in 12-tone equal temperament. The pitch trace shows whether a held note is settling, drifting, or moving with vibrato. This is a monophonic detector: it works best with one sustained pitch at a time. Chords, speech consonants, percussion, room noise, and strong overtones can make the displayed note jump because they do not present one stable fundamental. ## How to use it 1. **Allow the microphone** - Select Start microphone and grant access when your browser asks. The page analyzes the live stream locally. 2. **Make one clear pitch** - Sing, hum, whistle, or play a single sustained note close enough to the microphone to produce a steady signal. 3. **Read the result** - Check the note and octave, measured frequency, cents offset, signal clarity, and short pitch trace. 4. **Adjust the reference if needed** - Keep A4 at 440 Hz for common modern tuning, or choose 432 through 446 Hz to match an ensemble or recording. ## Who it's for - **Singers and vocal coaches** can check a starting note, sustain a target pitch, or watch how a note moves during vibrato. - **Instrumentalists** can identify a note from violin, flute, piano, brass, woodwind, or another pitched instrument without choosing a tuning preset. - **Music students** can verify ear-training answers and connect heard pitches with note names, octaves, frequencies, and cents. - **Producers and sound designers** can make a quick frequency check on a clean isolated tone before opening a larger audio editor. ## Expert note Autocorrelation looks for waveform repetition rather than simply choosing the loudest spectrum peak. That helps recover a fundamental whose overtones are louder, but a low note still needs a longer stable sample than a high note because each waveform cycle takes more time. ## Frequently asked questions ### Is microphone audio uploaded or recorded? No. The page requests a live microphone stream and analyzes short sample windows in browser memory. It does not create a recording or send your sound to a server. Select Stop listening, close the tab, or revoke site permission to release the microphone. ### Is this online pitch detector free? Yes. You can detect notes and frequencies without an account, download, subscription, or session limit. The microphone detector, cents meter, pitch trace, adjustable A4 reference, sample reading, and copy control are all available directly on the page. ### What pitch range and accuracy can I expect? The detector checks approximately 50 to 2,000 Hz, covering many sung and instrumental fundamentals. Accuracy depends on microphone quality, distance, room noise, and how stable the sound is. Readings are estimates, not calibrated acoustic measurements, and are most reliable for one clean sustained tone. ### Can the detector identify chords or a song key? No. This tool estimates one dominant fundamental at a time. A chord contains several simultaneous pitches, while a song key depends on relationships among many notes over time. Play isolated notes for this detector, and use a dedicated chord or key analysis tool for mixed music. ### What do cents sharp and flat mean? A cent is one hundredth of a semitone. Zero cents means the measured frequency matches the nearest equal-tempered note at the selected A4 reference. A negative result is flat and a positive result is sharp. Readings within about five cents appear centered. ### Why does the detected note jump? Background noise, vibrato, breath sounds, chords, and strong overtones can create several plausible repeating periods. Move closer to the microphone, reduce other sound, and hold one vowel or instrument note steadily. Let the initial attack settle before trusting the reading. ### Can I use A4 = 432 Hz instead of 440 Hz? Yes. Set the reference from 432 to 446 Hz. The nearest note, target frequency, and cents offset update against that reference. The measured hertz value does not change, but its relationship to the equal-tempered note grid does. ## Related tools - [Guitar Tuner](https://candoya.com/tools/guitar-tuner/) - [Spectrum Analyzer](https://candoya.com/tools/spectrum-analyzer/) - [Pitch Shifter](https://candoya.com/tools/pitch-shifter/) - [Tone Generator](https://candoya.com/tools/tone-generator/) - [Frequency Generator](https://candoya.com/tools/frequency-generator/) --- *Markdown edition of , published for AI agents and other automated readers. Index of key pages: .*