Voice Rater is an in-browser tool that analyzes voice recordings by measuring acoustic qualities like pitch stability, jitter, and formants to produce a 1-10 score without uploading data to servers. The scoring weights clarity, pitch stability, volume control, expressiveness, tone brightness, delivery flow, and range using fixed parameters derived from speech clinician methods. It also provides estimates of voice age and gender based on measurable acoustic changes, with results calibrated so ordinary healthy voices typically score in the sevens.