Whisper vs Deepgram vs AssemblyAI vs Speechmatics: Production Speech-to-Text APIs (2026)
After 90 days running production traffic on ServiceBot AI Helpdesk, here is my hands-on comparison of four STT APIs — Whisper, Deepgram Nova-3, AssemblyAI Universal-2, and Speechmatics Ursa 3 — with WER benchmarks on real Indonesian-English call audio, latency measurements at p95, and the hidden add-on stack that destroys budgets.