About Voice Rater

A free, independent voice analysis tool built on one principle: measure the voice honestly, and never take the audio off your device.

Why this site exists

There are plenty of places on the web that will rate your voice. Looking closely at how they work, most fall into one of two groups. Some upload your recording to a server for processing, which means your audio leaves your control entirely. Others do not appear to measure anything at all, and hand back a number that changes on every attempt regardless of what you said.

Voice Rater exists because there is a third option that nobody was offering: run genuine acoustic analysis locally, in the browser, and show the user every number behind the result.

What it actually measures

After you stop recording, your audio is split into 40-millisecond frames on your own device. Silent frames are discarded. Every remaining frame is analysed with the McLeod pitch method, a normalised autocorrelation, to extract your fundamental frequency. From there the tool derives:

• Jitter, cycle-to-cycle variation in pitch period, measured in the time domain by locating individual vibration cycles.
• Shimmer, the same variation applied to amplitude.
• Harmonic-to-noise ratio, derived from the normalised autocorrelation peak.
• Spectral centroid, computed with an FFT, describing tone brightness.
• Formants F1 and F2, extracted through LPC spectral envelope analysis on a downsampled copy of the signal.

These are the same parameters used in speech science and voice clinics. They are combined into the 1-10 score with fixed, published weights — clarity 24%, pitch stability 20%, volume control 14%, expressiveness 14%, tone brightness 14%, delivery flow 8%, range 6% — which are printed on the home page so anyone can check what drove their result.

How the score is calibrated

A scoring curve is a design decision, and it is easy to get wrong in both directions. Score everyone at nine and the number carries no information. Score everyone at four and the tool is simply rude.

The curve here was tuned against published clinical reference values for different voice conditions, so that a healthy adult voice recorded on ordinary consumer hardware lands in the sevens, a trained voice in a quiet room reaches the nines, a voice with a heavy cold falls to around five and a half, and genuinely disordered voice measurements drop near three. The result is deterministic: record the same passage twice in the same room and the score repeats to within a few tenths.

Your audio never leaves your device

Every calculation happens in your browser through the Web Audio API. There is no upload, no server-side processing, no account and no storage. Your recording exists only in the memory of your browser tab and is discarded the moment you record again or close it.

This is an architectural fact rather than a policy promise. The site is a set of static files with no backend to receive audio even if it wanted to.

Who runs it

Voice Rater is built and maintained by an independent developer working on small, focused web tools. There is no company behind it, no investors, and no data business. The site is free to use with no premium tier and nothing gated, and it is supported by advertising.

What this site is not

It is not a medical device and not a diagnostic service. Jitter, shimmer and harmonic-to-noise ratio are genuinely used in voice clinics, but there they are measured on calibrated equipment under controlled conditions and interpreted by a clinician alongside a physical examination. A five-second recording on a laptop is not equivalent, and no result here should be treated as a health assessment. If your voice is persistently hoarse for more than two or three weeks, see a doctor.

It also cannot tell you whether your voice is pleasant or attractive. Those are listener judgements shaped by accent, context and familiarity, and no signal-processing tool measures them.

Where to go next