Simultaneous translation: booth, RSI, or AI — and which tools for your meetings (2026)
"Simultaneous translation" is what everyone types; "simultaneous interpretation" is what the profession calls it. Both name the same thing: speech rendered in another language while it is being spoken — no pauses, no relay. But under that one term hide three very different ways of getting it — the human interpreter in a booth, remote simultaneous interpretation (RSI), and real-time AI translation — and three budgets that have nothing in common.
This guide separates the three, then compares named tools on a verifiable basis: what each vendor's public documentation states, with the source and the date we checked it. We build one of them (InterMIND); we'll say where it fits and where it doesn't.
The three forms of simultaneous translation
1. The interpreter in a booth (the historical standard)
Two interpreters per language pair, a soundproof booth, receivers for the room. This is how institutions and large conferences do it. The quality comes from a professional who understands context, irony, and jargon — and the cost comes from the same place: qualified humans, booked by the day, per language pair, plus equipment. For a weekly working meeting, this setup simply isn't designed to apply.
2. RSI: the human interpreter, remote
Remote-simultaneous-interpretation platforms (Interprefy, KUDO, Boostlingo) deliver human interpreters' audio — sometimes with an AI option alongside — to participants' phones or headsets, on site or in a video call. The setup remains an event: one speaker, an audience, languages fixed in advance, interpreters booked.
3. AI simultaneous translation
No interpreter here: a speech-recognition → machine-translation → speech-synthesis cascade renders the speech in each listener's language within seconds, with nothing to book. This is the only form whose marginal cost fits an ordinary meeting — the category's tipping point. The question then becomes: what does the tool translate, beyond the voice?