SyncMySubsMake bilingual subtitles
Stack two languages into one subtitle file, so you can watch with both on screen at once. Perfect for language learning. Add a file for each language below and it combines instantly in your browser, with nothing uploaded.
Add a file for each language to stack them.
Watch with two languages at once
Bilingual subtitles put two languages on screen together — usually the original audio's language and your own. For anyone learning a language, it is one of the most effective ways to watch native content: you follow the dialogue in the language you are studying and glance at the translation only when you need it. This tool takes two ordinary subtitle files, one per language, and stacks them into a single track your player can show.
Add the language you want on top to the first slot and the second language below it. Cues that overlap in time are combined so both lines appear together, and you can export the result as SRT, VTT, or ASS.
For the cleanest result, both files should be timed to the same video. If one language is a little early or late, line it up first with the Shift tool, or use Framerate if it drifts over the runtime, then come back and stack them.
Need the general two-file merger instead (including joining clips in sequence)? Merge subtitles →
FAQ
What are dual-language (bilingual) subtitles?
Dual-language subtitles show two languages on screen at the same time — for example the original dialogue and your native language stacked together. Language learners use them to follow a film in the language they are learning while keeping a translation in view. This tool builds one by combining two separate subtitle files into a single track.
Which language ends up on top?
The file you add to the first slot is stacked on top, and the second file goes underneath. Overlapping cues are combined into one so both lines appear together. If you want the other order, just swap which file goes in which slot.
Do the two files need to have matching timing?
They should be roughly in sync for the same video, since cues are stacked by when they overlap. If one language is offset, fix it first with the Shift tool (or Framerate if it drifts), then stack. Two subtitle tracks ripped for the same release usually line up already.
What subtitle formats can I combine?
You can drop in SRT, VTT, ASS, or SUB files, and export the combined track as SubRip (.srt), WebVTT (.vtt), or Advanced SubStation Alpha (.ass). The two files can even be different formats.
Is my file uploaded anywhere?
No. The files are combined in JavaScript inside your browser. They never leave your device, no server is involved, and the page keeps working even if you go offline.