How to merge subtitles into a bilingual file
Drop the first subtitle file, open the Merge tab, choose the second file and pick a mode. Both files are read with their own detected encodings, so mixing, say, an English UTF-8 file with a Russian Windows-1251 file works. Then download the result in any format.
Stacked vs interleaved
- Stacked puts each cue of the second file under the cue of the first it overlaps most in time, on a second line in a smaller size. It suits language learning, because both languages are on screen together.
- Interleaved keeps every cue from both files with its own timing and sorts them together. Players will show overlapping cues at the same time, and it works best when both files were timed to the same video.
- In stacked mode, cues from the second file that overlap nothing in the first are kept as their own cues so no text is lost.
Bilingual subtitles for language learning
Watching with two subtitle lines — your target language and your own — lets you read along, look up what you missed and build vocabulary without pausing. The two files must be timed to the same cut of the video; if the second one is late or early, sync it first with the subtitle sync tool.
How the smaller second line is drawn depends on the format. ASS supports it directly, WebVTT uses a STYLE rule that the converter adds, and SRT uses a font size tag that not every player honours; if your player ignores it, the two lines simply appear at the same size.
Where merged files work
- VLC, mpv and MPC-HC read merged SRT and ASS files.
- Web players with WebVTT support show the merged track, including the smaller second line.
- Some TVs and media boxes show both lines at the same size.
How to use it
- Drop the first subtitle file onto the box.
- Open the Merge tab and choose the second file.
- Pick stacked or interleaved and click Merge.
- Download the bilingual file in the format you need.
Frequently asked questions
How do I combine two subtitle files?
Load one file, open the Merge tab, choose the second and click Merge. The result can be downloaded as SRT, VTT, ASS or SBV.
Do the two files need matching timing?
They should be timed to the same version of the video. If one is off, correct it first with the sync tool, then merge.
Can the two languages have different encodings?
Yes. Each file’s encoding is detected separately.
Why is the second line not smaller in my player?
Not every player supports size changes in SRT. ASS and WebVTT handle it best; in others both lines show at the same size.
Is my subtitle file uploaded?
No. The file is read and converted in your browser and is never sent to a server. The site records only an anonymous count of the format pair and a rough size bucket, never the subtitle text.