SubMate
Optional cloud translation

Bring your own AI provider, only if you want to.

SubMate defaults to Chrome's on-device translation. Cloud translation is a separate, explicit choice for people who want a selected model's context-aware output.

Enable a provider

  1. Open Options → Translation and choose Cloud API.
  2. Select a provider and enter your own API key.
  3. Approve Chrome's request for access to that provider host.
  4. Optionally specify a model; otherwise SubMate uses the provider default.

What is sent

The selected provider receives subtitle text from the current episode, source and target language, and a small amount of preceding subtitle context. SubMate never sends cookies, authorization headers, signed media URLs, audio, video, page URLs, viewing titles, or browsing data.

Key handling

Keys are stored locally in chrome.storage.local, separately for each provider. They are not synced, the content script never receives them, and saved keys are never rendered back into the options-page DOM. Requests go directly from your browser to the provider—there is no SubMate proxy.

Providers

Google Gemini, OpenAI, Anthropic, Mistral, DeepSeek, xAI, Groq, OpenRouter, and compatible custom endpoints are supported. Custom endpoints must use HTTPS except for localhost and 127.0.0.1.

For operational detail and current defaults, read the repository's cloud translation documentation.