SonicCaption

SonicCaption is a Chrome/Edge extension that adds low-latency, real-time captions and instant translation as an overlay on top of whatever you’re already watching or attending—YouTube videos, online courses, livestreams, Zoom/Google Meet web sessions, and more. Instead of being tied to a single platform, SonicCaption works across sites so you can understand content and conversations in your preferred language without changing your workflow.

It’s designed for language learners, international teams, and anyone who needs fast, readable subtitles while watching or meeting in a non-native language. You can show bilingual subtitles (original + translation) to learn naturally, or switch to translation-only for maximum focus.

Key features

Real-time captions: live speech-to-text overlay while you watch videos or join meetings

Instant translation: translate captions into your target language in real time

Bilingual mode: show original + translated subtitles together (great for learning)

Translation-only mode: show just the translated line for a cleaner view

Low-latency experience: optimized to keep captions feeling “live,” not delayed

Works across sites: use the same caption/translation overlay on many video and meeting pages

Customizable subtitle styles: adjust font size, spacing, opacity/background, and overall readability

Flexible placement: move/position the caption overlay so it doesn’t block important content

Fullscreen friendly: designed to keep captions visible while watching in fullscreen

Multi-language support: built for switching between different source/target languages, including RTL-friendly layouts for languages that need it