ElevenLabs explains how voice activity detection works and where it fits

Key points

• VAD outputs a yes-or-no decision on speech in each frame, typically 10-30 milliseconds, without outputting words.
• The process runs as a five-stage loop: capture, framing, feature extraction, scoring from 0 to 1, and state decision.
• Traditional VAD uses energy thresholds and can false-trigger on loud noise; neural and semantic AI variants handle noise and context better.
• Endpointing, not VAD, decides whether a speaker has finished a thought; the two are complementary technologies.

Why it matters for marketers: Content teams using voice agents or transcription should benchmark VAD on noisy, real-world calls rather than clean recordings, since false positives and negatives affect results.