Translation modes
- Bilingual: original subtitles and their translation together.
- Translation only: translated subtitle text without duplicate source text.
- Off: remove the SubMate overlay without losing your chosen settings.
Playback-aware rendering
SubMate preserves subtitle cue timing, tracks video progress, adapts to fullscreen, respects right-to-left languages, and hides its translated overlay during ad breaks before re-synchronizing to the content.
Local cache and import/export
Episode subtitle sources and translations are cached in IndexedDB for fast reload recovery. You can export or import validated SubMate JSON, SRT, and VTT packages for translation workflows beyond the languages Chrome can translate on-device.
Language and appearance controls
The interface is localized in English, Japanese, Arabic, and French. The options page offers source-language preference, subtitle style, themes, cache management, and import/export controls.
Privacy-first defaults
There is no SubMate account, backend, analytics, or bundled API key. Cloud translation is optional, uses a key you supply, and requests access only to the selected provider host.