It watches your library, judges every subtitle, and installs the one that fits.

Self-hosted subtitle automation for multiple languages — seven sources across languages, with the deepest Chinese catalog coverage available.

AGPL-3.0 · one Docker container · your keys stay on your server

Try the live demo

What it searches, and what it checks

Seven sources across languages

OpenSubtitlesGeneral coverage across 105 languages.
SubDLInternational catalog; free API key.
ASSRTChinese-focused archive; free API key.
R3SUBOfficial Traditional Chinese tracks from Taiwan releases.
JimakuJapanese-focused source.

Plus SubHD and Zimuku, two keyless Chinese community sources that ship disabled by default. The setup wizard only shows the sources relevant to your target language.

Identity and timing checks

Every candidate is checked against the actual video before it’s installed — the right title and episode, with timing that lines up. A candidate that fails never touches your library.

capability

TMDB identification

Filenames lie. Before any source is searched, every file is resolved to a real title against TMDB — the right movie, the right season, the right episode.

capability

LLM translation

No usable subtitle in your language? The translation lane produces one from a Japanese or English source, using your own LLM key.

No media server required

It scans your folders directly and writes the subtitle next to the video file. Jellyfin, Emby, and Plex pick it up — but none of them is required.

Language coverage, in plain terms

Chinese — the deepest coverage: four dedicated sources.
Japanese — a dedicated source (Jimaku).
The other eight selectable languages (EN/KO/ES/FR/DE/PT/RU/IT) — equally first-class in the pipeline, with search covered by OpenSubtitles’ 105 languages and SubDL’s international catalog.

Non-Chinese sources are thinner today. If you want your language covered better, a provider adapter is a narrow, well-defined contribution: the interface is four members — name, enabled, search, resolve — and fits on one screen.

How a subtitle gets installed

Discover

It scans your media folders directly — no Jellyfin, Emby, or Plex required — and finds every title that’s missing a subtitle in your target language.

Subtitle Scout media library: a dense wall of poster art with a subtitle status bar and download counts under each title — The library wall — a green bar means the title is covered; amber means it’s still waiting.

Judge

It searches the sources relevant to your target language, then ranks and verifies candidates against the actual video — identity and timing — before picking one.

Subtitle Scout title detail page: poster, year, and a legend of per-title verdicts such as subtitled, native language, embedded track, translating, and retry later — A title that needs nothing gets left alone — “native language, no subtitle needed” is a verdict too.

Install

The chosen subtitle is written next to your video file, named so any player picks it up. When no usable source exists, the LLM translation lane can produce one.

Subtitle Scout activity page: automatic check status, subtitle and translation tabs, and a queue of titles waiting for subtitles — The activity page: a subtitle lane and a translation lane, working through the queue on their own.

The full dashboard runs on your phone, with bottom-tab navigation.

Subtitle Scout on a phone: the activity view with bottom tab navigation

Up and running in one command.

Runs anywhere Docker does — a NAS, a home server, or a VPS. Configure TMDB, your subtitle sources, and your LLM through the setup wizard after it starts; no credentials go in the compose file.

# docker-compose.yml
services:
  subtitle-scout:
    image: ghcr.io/fancydirty/subtitle-scout:latest
    restart: unless-stopped
    ports:
      - "8099:8099"
    volumes:
      - /:/hostroot      # browse and pick media folders from the dashboard
      - ./cache:/cache
    environment:
      TZ: Asia/Shanghai

# then
cp .env.example .env
docker compose up -d

If ghcr.io is slow or blocked from mainland China, swap the image prefix for the mirror:

image: ghcr.1ms.run/fancydirty/subtitle-scout:latest

Full setup guide on GitHub

Before you install

Do I need my own API keys?: Yes. TMDB is required and free; ASSRT is strongly recommended for Chinese coverage and also free. You bring your own keys and control your own usage — nothing is proxied through anyone else’s server.
Is this only for Chinese subtitles?: No. Any of the ten selectable target languages works end-to-end, and the setup wizard derives which sources matter for yours. Chinese simply has the deepest catalog — four dedicated sources — Japanese has its own, and OpenSubtitles and SubDL cover the rest. The translation lane can fill the gaps.
Do I need Jellyfin, Emby, or Plex?: No. Subtitle Scout scans your filesystem directly and writes subtitle files next to your videos — any media player picks them up on its own.
What’s the license?: AGPL-3.0. And because it’s self-hosted, your media library, your credentials, and your viewing habits never leave your own server.

See it running.

Interactive demo — a sample library, read-only, no sign-in.

Try the live demo