Help & answers
Frequently asked questions
The essentials on finding synchronized subtitles, translating them and keeping your profile private.
Why do I need OpenSubtitles credentials?
SubTranslate currently uses your authenticated OpenSubtitles connection to search for and download release-matched subtitle sources. This gives each profile its own provider access and makes the search and download flow more predictable. Gemini is separate and is required only when you create a new translation.
Can I use the official OpenSubtitles V3 addon instead?
Not currently. The public V3 addon is convenient because it does not need a personal login, but it can expose different results and be rate-limited. SubTranslate currently uses the authenticated route for consistency. An optional best-effort V3 source is being considered for a future update.
Is it possible to self-host the addon?
Not currently. SubTranslate is offered as a hosted service, and there is no public self-hosting package or source release at the moment. An official self-hosted option may be considered in the future, but there is no timeline for it.
Does SubTranslate translate subtitles directly from my stream or another addon?
No. A subtitle addon needs an actual text subtitle source to translate. SubTranslate does not read an embedded or another addon's loaded subtitle text or extract media tracks on the public server.
How does SubTranslate keep subtitles in sync?
It ranks OpenSubtitles candidates against the video hash or release filename, then Gemini translates only the cue text. Each cue keeps its original start and end time.
Can a completed translation be reused by other viewers?
Yes, but only when it is safe. Reuse prefers an exact video-hash match. When no hash is available, the fallback requires the same normalized release filename and content ID. A title ID alone is never enough to reuse a subtitle for a different release.
Do I always need a Gemini API key?
No. Gemini is needed only to create a new AI translation. If SubTranslate finds subtitles already available from OpenSubtitles in your selected language, it can serve that subtitle without translating it.
How many Gemini requests does a translation use?
SubTranslate uses Gemini 3.5 Flash-Lite by default and translates subtitle text in bounded batches. The exact number of requests depends on subtitle length, number of cues and any retries. In a test of four films and two TV episodes, 6,940 subtitle cues used 73 Gemini requests in total, or about 12 requests per title on average. Individual titles used between 6 and 20 requests. As a dialogue-heavy example, 12 Angry Men used 28 requests. On the current Gemini free tier, eligible accounts can receive up to 500 requests per day. Even with a conservative estimate of 20 requests per film, that is roughly 25 translations in a day. Google can change quotas by model, account or region, so check your current limit in Google AI Studio. Based on these tests, most normal viewers should be unlikely to reach the daily limit with Flash-Lite.
What happens while a translation is in progress?
Selecting a virtual target-language track starts or returns the matching job. While it is queued or translating, SubTranslate returns a status message. Reopen the subtitle menu when the job has finished to choose the completed track.
Which languages and clients are supported?
Each profile can select one of the Gemini-supported target languages. English is the current AI source language. SubTranslate is designed for Stremio/Nuvio and compatible clients that support external WebVTT subtitle tracks; how labels are displayed can vary by app and version.
How do I manage the same profile on another device?
After creating a profile, save the profile ID and password. You can use them on the configuration page to recover and manage the same profile from another browser or device.
Are my credentials private?
Provider credentials are encrypted on the server and are never embedded in your public Stremio manifest URL. Read the privacy and security details.