Stremio subtitles: fixing streams and adding your own to local videos
Stremio subtitles break in two completely different ways depending on what you're watching: an addon's subtitle track failing on a streamed title, or your own local video file simply having no matching subtitle for Stremio to find. Here's how to fix both.
Subtitles not working on a streamed title
When you're streaming through an addon (OpenSubtitles and similar), a few things account for most subtitle failures:
- Multiple subtitle addons installed at once — if one is broken or slow, it can block or override results from a working one. Try disabling all but one subtitle addon and see if the problem clears.
- No subtitle exists for that exact release — subtitle addons match subtitles to a specific file/release, so an obscure title or an unusual rip may simply have nothing available.
- Wrong default language — check Settings → Subtitles and confirm your preferred language is actually selected, not just installed as an option.
- Timing drift — Stremio's player has a built-in delay adjustment (commonly the G/H keys, or a slider in the subtitle menu on other builds) to nudge subtitles earlier or later without needing a different file.
If the addon genuinely has nothing for a title, you're not stuck — Stremio's player also accepts a subtitle file you drag directly onto it during playback. Anything you've extracted, generated or fixed with AI Subtitle Studio works the same way as an addon-supplied one once it's loaded.
Playing your own videos: why the subtitle doesn't show up
Stremio can also play video files from your own computer through its local-files/Board feature — this is where AI Subtitle Studio is directly useful, since it's working with a file you actually have. For Stremio to auto-load a subtitle for a local video, the subtitle file needs to sit in the same folder and have the exact same filename as the video, differing only in extension — for example Episode.12.mkv paired with Episode.12.srt. A mismatched filename (a language code appended, different capitalization, extra text) is the single most common reason a subtitle silently fails to load for local playback, and it's worth checking before assuming anything is actually broken.
Which subtitle format actually works for local playback
SRT is the safest bet for Stremio's local player — plain text, universally supported. VTT generally works too. Styled .ass/.ssa subtitles (common on anime rips) may not render their styling correctly outside a dedicated .ass-aware player, and image-based subtitles (.sup from Blu-ray, .sub/.idx from DVD) aren't text at all, so Stremio can't display them as-is. If you're starting from any of those, convert to SRT first — see converting subtitles to SRT for text-based formats, or SUP to SRT and SUB/IDX to SRT for image-based ones, which use built-in OCR to turn the picture-based track into real text.
Getting a subtitle onto a local video that has none
If your local file has no subtitle at all — an embedded track, a sidecar file, anything — check the video itself first: MKV files especially often carry a subtitle track you don't see until you look, covered in extracting subtitles from MKV. If there's genuinely nothing there, AI transcription generates a fully timed subtitle straight from the audio, offline. And if you found or generated a subtitle in the wrong language, AI translation converts it to yours while keeping every timestamp intact.
Downloaded a subtitle that doesn't match your file's timing
A subtitle pulled from a site like OpenSubtitles is often timed for a different release of the same movie or episode than the file you have, so it drifts out of sync from the first line. Rather than manually calculating an offset, Sync Subtitles matches the file to your video's actual audio and re-times every line automatically — then rename the result to match your video's filename so Stremio picks it up.
How to get a matching subtitle onto a local video for Stremio
- Check the video for an existing track Add the file to AI Subtitle Studio — MKV rips especially often already have an embedded subtitle you can extract in one click.
- Generate one if there's nothing No track anywhere? Run AI transcription to produce a fully timed subtitle from the audio.
- Convert to SRT if needed If the subtitle is .ass, .sup or .sub/.idx, convert it to plain .srt so it displays reliably in Stremio's local player.
- Fix the timing if it drifts Downloaded a subtitle from elsewhere? Run Sync Subtitles to re-time it to your exact file before moving on.
- Rename to match the video exactly Save the .srt in the same folder as the video with the identical filename, changing only the extension, then refresh Stremio's local library.
Get a working subtitle file for free
Free to try on Windows & macOS · full version $9.99 one-time · 100% offline