Live captions and translation for any Windows audio local

Real-time captions and translation for any audio on your Windows PC — fully local, no cloud.

AnyCaptions listens to the audio you are already hearing — games, videos, calls, any app — and shows a floating caption overlay on top of everything. Speech recognition and translation run entirely on your machine: no audio or text ever leaves your computer, and the app works offline once installed.

Live transcription of system audio via WASAPI loopback — no microphone or virtual cable needed, just pick the output device you already use

Real-time translation into 37 languages, from Portuguese to Japanese, with automatic detection of the spoken language

Fast English ↔ Portuguese path on the CPU (~90 ms per sentence), with the full 37-language model on the GPU

Voice dictation — speak and your words are typed into whatever application you are using

Transparent, click-through overlay — when locked, clicks pass straight through the caption; recover it any time from the tray or the global shortcut (Ctrl+Alt+L, configurable)

In-app model download — the large translation model is a one-click download with integrity verification; everything else ships in the installer

Customizable captions: size, colors, width and position

UI in 6 languages: Portuguese (Brazil), English, Spanish, French, Russian and Simplified Chinese

Private by design: no history, no telemetry, nothing sent to the internet

Tech stack

Desktop app (backend/ + frontend/): Rust + Tauri v2, Vanilla TypeScript + Vite

Website (site/): Astro frontend + ASP.NET Core API + PostgreSQL

Models

All models run locally:

Inference runs on NeMo-Speech.cpp (Apache-2.0) for recognition and Riva, and on CTranslate2 (MIT) for OPUS-MT.

Licenses: Nemotron under OpenMDW-1.1; Riva Translate — Licensed by NVIDIA Corporation under the NVIDIA Open Model License; OPUS-MT under CC-BY-4.0 (credits: Helsinki-NLP/OPUS-MT, Jörg Tiedemann). Selector flags from flag-icons (MIT).

Prerequisites: stable Rust (x86_64-pc-windows-msvc, 1.90+), Visual Studio C++ tools with the Windows SDK, WebView2 and Node 24.15+.

npm.cmd --prefix frontend ci npm.cmd --prefix frontend run tauri -- dev

Models and the inference libraries are not required to compile — only to transcribe and translate (see backend/models/README.md).