A Browser Voice API is a set of web-standard interfaces (chiefly the Web Speech API's SpeechRecognition and SpeechSynthesis, plus getUserMedia and the Web Audio API) that let web apps capture microphone audio, transcribe speech, and synthesize spoken output directly in the browser — no native install required. They give web developers on-device or cloud-backed speech features behind a simple JavaScript API. Browser support and accuracy vary, so many production apps pair them with a server-side speech model.
Browser voice APIs make it possible to add voice input, dictation, and read-aloud features to any web app, powering lightweight voice assistants and accessibility tools. They lower the barrier to voice because everything runs client-side in JavaScript. For higher accuracy, low latency, or consistent cross-browser behavior, teams often stream audio to a dedicated ASR/TTS service instead.