The short answer
If your library is English-language live-action and Bazarr already covers it, keep Bazarr. It is more mature, has more hands on it, and does that job well. Replacing a working setup with a younger tool buys you very little.
Sublarr earns its place when anime is involved — absolute episode ordering, AniDB resolution, ASS subtitles kept as ASS, and files carrying several English tracks where the wrong pick desyncs what you read from what you hear.
Where the engineering went
Everything below links to the page documenting it, so you can check the claim rather than take it.
Anime-first matching
Releases numbered straight through a series instead of per season are the normal case, not the exception. Sublarr resolves series against AniDB in four tiers and searches providers with both numbering schemes.
The format, not just the file
ASS stays ASS — positioning, fonts and typeset signs intact — rather than being flattened to SRT. Signs-and-songs and forced tracks are classified, not guessed at.
Retiming against the audio
A waveform editor with speech detection and snap targets, for the cases automatic sync gets wrong. Two sync engines — ffsubsync and alass — run as a fallback chain, with a per-file audit trail of which one was used.
Translation that stays local
When no subtitle exists at all, a local LLM through Ollama can produce one you can inspect and edit, with a translation memory and a per-series glossary. Off by default, and labelled experimental for good reason.
Where Sublarr is behind
- Maturity and reach. Bazarr has years of production use and thousands of installations. Sublarr is solo-maintained and much younger — that difference is real and it matters when something breaks.
- No user accounts. One shared password, no roles, no per-user audit trail. For genuine multi-user setups, put it behind a reverse proxy that authenticates for it.
- One instance per library. No worker pool, no multi-host distribution. One container per library.
- Translation is experimental. Quality varies sharply by backend, model and language pair. Never point it at a library you have no backup of.
Common questions
Should I switch from Bazarr to Sublarr?
Probably not, if Bazarr is working for you. Bazarr is more mature, has far more people behind it, and covers English-language live-action well. Sublarr is worth the change when your library has anime in it — absolute episode ordering, AniDB resolution, ASS subtitles with their styling intact, and several English tracks per file where picking the wrong one desyncs what you read from what you hear.
What does Sublarr do that made it worth building?
Four things: anime-first matching (absolute ordering and AniDB resolution, so the right episode is found for releases numbered straight through a series), format fidelity (ASS kept as ASS with styling, not flattened to SRT), a waveform editor for retiming cues against the actual audio, and subtitle translation through a local LLM via Ollama so nothing leaves your machine. Translation is off by default and labelled experimental.
Can I run Sublarr and Bazarr at the same time?
Yes, but point them at different language profiles or different libraries. Both write sidecar subtitle files next to your media, so two tools chasing the same missing subtitle will overwrite each other's work. A common split is leaving live-action with Bazarr and giving Sublarr the anime library.
Why do anime subtitles need a different tool at all?
Because three things break the normal assumptions. Episodes are often numbered absolutely across a whole series rather than per season, so a season/episode lookup finds nothing. Fansub releases ship ASS with positioning, fonts and typeset signs that a conversion to SRT destroys. And a single file can carry several English tracks — full subs, signs-and-songs, and a dubtitle track matching the English dub — where the wrong pick silently contradicts the audio.
What is Sublarr worse at?
Maturity and scale. Bazarr has years of production use and thousands of installations behind it; Sublarr is solo-maintained and much younger. Sublarr also has a single shared password rather than user accounts, assumes one instance per library, and has no auto-update. All of it is written up on the Scope and limitations page rather than buried.
Try it against one library
Point Sublarr at your anime folder and leave the rest where it is. One Docker container, web UI on port 5765.