Online frequency detector

What is an online frequency detector?

An online frequency detector measures how fast sound waves vibrate each second and shows the result in Hertz (Hz). This hosted Hz meter uses your microphone and autocorrelation to estimate the fundamental frequency of singing, humming, speech tones, whistles, or steady instrument notes. Unlike a chromatic tuner that rounds to note names, this frequency meter focuses on raw Hz readings with two decimal places—useful for tuning checks, acoustics demos, and ear training alongside tools like /sound-memory-game.

Frequency detector features

Real-time Hz measurement with session stats and waveform preview.

1. Live Hz readout: Current frequency updates continuously while detection runs—no upload step.
2. Min, average, and max: Session stats track the lowest, mean, and highest Hz captured during a run.
3. Oscilloscope waveform: See the incoming audio wave so you can spot steady tones versus noisy input.
4. Copy Hz values: One-click copy for the live reading or common reference frequencies.
5. Autocorrelation engine: Estimates fundamental frequency (F0) from the microphone time-domain signal.
6. Browser-only processing: Audio stays on your device—nothing is recorded or sent to a server.

How to use the Hz detector

Start measuring frequency in a few seconds.

1. Start detection: Click Start detection and allow microphone access when prompted.
2. Produce a steady sound: Sing one note, hum, whistle, or play a single instrument pitch toward the mic.
3. Read and copy Hz: Watch the live Hertz value and session min, average, and max. Copy Hz when you need the number elsewhere.
4. Stop when finished: Click Stop detection to release the microphone and reset the session stats.

Tips for accurate frequency measurement

Get cleaner Hz readings from the sound frequency meter.

1. Use a quiet room: Fans, traffic, and room hum raise the noise floor and can hide the tone you want.
2. Hold one pitch: The detector works best on steady tones—not fast melodies or percussive hits.
3. Stay close to the mic: A consistent distance helps level stay above the silence gate.
4. Disable aggressive processing: This tool requests raw-ish mic input; system “voice enhancement” can skew readings.
5. Compare with references: Use the built-in 440 Hz and middle C references when calibrating by ear.
6. Practice recall on /sound-memory-game: After measuring Hz, train pitch memory with the five-round frequency recall game.

Frequently Asked Questions

Have questions? We have answers.

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