Privacy, plainly.
Your voice
In the browser, speech-to-text uses your browser's built-in Web Speech API — audio is processed by your browser vendor's speech service (e.g. Google for Chrome), not by us. In the Mac app, transcription runs entirely on your device via whisper.cpp; audio never leaves your machine.
Your text
When AI cleanup is on, the transcript text (only text, never audio) is sent to our cleanup API and forwarded to an AI provider — Anthropic (Claude) or Groq (Llama) — to be polished. We don't store transcripts on our servers. Turn AI cleanup off in Settings and everything stays local.
Your history
By default, dictation history lives in your browser's localStorage on your device only. If you turn on sync (optional), your history is stored in our database keyed to a long random secret. Only devices holding that secret link can read it — there are no accounts and we never see who you are. Clear it anytime.
No accounts, no tracking
MouthPiece has no login, no email, no password. Sync works via a private link you choose to share between your own devices. No cookies for tracking, no ads.