Combined Subtitles

Combined subtitles merge the sidecars of two or three languages into a single bilingual file, so both languages appear on screen at once — one language positioned above the other. This is useful for language learning, or for watching with a native and a foreign track side by side.

Sublarr never touches your original per-language sidecars. A combined file is a new, separate artifact written next to the video.

Combined subtitle composition

What it does

For a given video, Sublarr picks the best sidecar for each requested language, runs each one through the subtitle security sanitizer, and composes them into one file. The first language you list is the primary — order matters.

When several sidecars exist for the same language, Sublarr picks by source priority: a plain sidecar wins over a hearing-impaired (HI/SDH) one, which wins over a forced one.

Output formats

You choose the output format:

• ASS — each language is overlaid in the same script and pinned to a vertical position with an alignment tag (primary at the bottom, secondary at the top by default). Every input’s styles are kept under a per-language namespace, so a shared Default style name in one language never overrides the other’s formatting.
• SRT — the aligned cues are stacked under the primary language’s timestamps, one language per line, with the top-positioned language first.

Supported source formats are ASS, SSA, SRT and VTT. Bitmap subtitle formats (PGS, VobSub, DVD subtitles and similar) cannot be combined as text and are rejected.

Note

Position control (primary/secondary placement) applies to ASS output only. SRT has no positioning; its stacking order follows the same top-to-bottom intent.

Timing alignment

The two tracks rarely share identical cue timings, so Sublarr aligns them automatically:

Situation	How cues are paired
Both tracks have the same number of cues	Paired one-to-one by index
Cue counts differ by a constant shift	Paired with that offset applied
Neither of the above	Paired by time overlap

The primary track’s timestamps always drive the combined file; the secondary language’s text is attached to the primary cues it lines up with.

Combine on demand

From a series, open an episode’s action menu and choose Combine Subtitles. The dialog lets you:

• Pick 2–3 languages (present sidecars and profile target languages are offered; the first is primary).
• Choose the output format (ASS or SRT).
• Optionally enable Translate & combine a missing language — if a requested language has no sidecar yet, Sublarr generates it via the translation stack first, then combines. This requires translation to be enabled.

If a requested language is missing and translation is not enabled, the dialog warns you and the operation fails rather than writing a partial file.

Tip

You can also combine many items at once. The batch endpoint reports each item independently — an item that is missing a language is reported as skipped, so one gap never fails the whole batch.

Combine automatically

Each language profile can combine automatically after a subtitle is downloaded or extracted. Configure this under Settings → Language Profiles, in the Combined subtitles section:

Setting	Default	Effect
Combine automatically	Off	Merges the selected languages into one bilingual file after each download/extract
Languages to combine	(none)	A subset of the profile’s target languages; the first is primary (order matters)
Format	ASS	Output format for the combined file (ASS or SRT)
Position (ASS only)	Primary bottom, secondary top	Vertical placement of each language in ASS output

Automatic combining never translates: if one of the selected languages is not present, the item is silently skipped. Sublarr also skips work when an up-to-date combined file already exists — it only rewrites when a source sidecar is newer than the current combined file.

The output file

The combined file is written next to the video, alongside your existing sidecars, using this naming convention:

<video-stem>.<lang1>-<lang2>[-<lang3>].combined.<format>

For example, combining German and English into ASS for Show.S01E01.mkv produces Show.S01E01.de-en.combined.ass.

The file is recorded as a managed subtitle with the source combined. Because it is composed from sidecars that were already counted when they arrived, it does not inflate your download statistics or success rate.

Caution

The combined filename intentionally does not look like a single-language sidecar (the de-en tag is not a language code), so the keep-languages cleanup never mistakes it for an unwanted track and trashes it. Do not rename combined files to a plain single-language pattern, or cleanup rules may remove them.