How-to
How to create bilingual subtitles
Last updated: 2026-06-11
To create bilingual subtitles, upload your .srt or .vtt file, pick the second language, turn on the Bilingual option, and download. The result is one file where each cue holds two languages — the original line and its translation stacked under the same start and end time — so they appear together and stay in sync with the video. Unlike a browser extension that only works inside Netflix or YouTube, this is a portable file you can play in VLC, mpv, Plex, or on a TV.
Dual-language subtitles are the most-requested setup for language learners: you read a reference line in a language you know while hearing and reading the one you are studying. Below is the four-step process, where the file works, and how it differs from overlay tools like Language Reactor.
Drop your subtitle file here, or click to browse
Supports .srt, .vtt, and .ass / .ssa
The four steps
- 01
Upload your subtitle file
Open the translator and drop in the .srt or .vtt file you already have — for example a Japanese track from Kitsunekko or the original English captions. Each cue's timecode is locked before any text changes.
- 02
Pick the second language and turn on Bilingual
Choose the target language (the one you want stacked alongside the original) and tick the Bilingual option. The source language is auto-detected, so you only set the language you are adding.
- 03
Choose which line goes on top
Decide whether the original or the translation sits on top. Learners usually keep the language they are studying on top and their native language underneath for reference.
- 04
Translate and download
Run it. Each cue now holds both languages under the same start and end time, so the file stays in sync. Download the .srt or .vtt and load it in VLC, mpv, Plex, or on a TV — no browser extension needed.
Bilingual file vs. browser overlay
Overlay extensions and a downloadable bilingual file solve different problems. This is when each one fits.
| Need | Bilingual file (SubLingo) | Overlay extension |
|---|---|---|
| Streaming in a browser | Works (load the file) | Works |
| VLC / mpv / Plex / TV | Works | No |
| Your own video files | Works | No |
| Offline / no internet | Works | No |
| Keep a permanent copy | Yes — it is a file | No |
Where bilingual subtitle files are used
Immersion learners studying Japanese, Korean, Spanish, or any language download a native subtitle track, add their own language as a second line, and watch in a desktop player. The same file works for a foreign film you own, a downloaded lecture, or anything a browser extension cannot reach. If you start from a single-language track, see how to translate an SRT file first, then come back and add the second line.
Which language on top?
There is no single right answer, so SubLingo lets you choose. A common setup is the language you are learning on top, with your native language underneath as a quick check. If you only glance at the translation when stuck, put it on the bottom; if you are an early beginner leaning on it, put it on top. The cue timing is identical either way — only the line order changes.
Key facts
- A bilingual file holds two languages per cue under one timecode.
- It is a portable .srt/.vtt file — works in VLC, mpv, Plex, TVs, offline.
- Browser overlays (Language Reactor, Trancy) only work inside a streaming tab; a file works anywhere.
- You choose the order: original on top or translation on top.
- Timecodes are never changed, so both languages stay in sync.
- Free, no signup, 100+ target languages.
Definitions
- Bilingual subtitles
- One subtitle file showing two languages per cue — original and translation stacked under a single timecode.
- Dual subtitles
- Another name for bilingual subtitles; common in language-learning communities.
- Immersion learning
- Watching native content in a target language; a reference line in a known language helps comprehension.
- Soft subtitles
- A separate sidecar
.srt/.vttfile the player overlays — what you download here, as opposed to burned-in text. - Cue
- A single timed subtitle entry; in a bilingual file each cue holds both languages.
- Order
- Which language sits on the top line — original-first or translation-first.
Related guides
FAQ
What are bilingual subtitles?+
Bilingual (or dual-language) subtitles show two languages at once for the same line of dialogue — for example the original Japanese on top and an English translation underneath. Both sit under one timecode, so they appear and disappear together. They are popular with language learners who want to read along in a language they know while hearing the one they are studying.
How do I make a bilingual subtitle file?+
Upload your .srt or .vtt to SubLingo, pick the second language, turn on the Bilingual option, choose which language goes on top, then translate and download. The result is a single file where each cue contains the original line and the translation stacked together, with the original timecodes untouched.
How is this different from Language Reactor or a browser extension?+
Browser extensions like Language Reactor or Trancy overlay dual subtitles inside a streaming site such as Netflix or YouTube. They cannot help with your own files. SubLingo produces a portable bilingual file you can use anywhere — VLC, mpv, Plex, a smart TV, or an offline copy of a film — not just inside a browser tab.
Will the two languages stay in sync with the video?+
Yes. The translation is written into the same cue as the original, so both share one start and end time. SubLingo never changes the timecodes, so the bilingual file is as accurately timed as the source.
Can I put the translation on top instead of the original?+
Yes. There is a toggle to choose the order. Put the language you are learning on top and your reference language below, or the other way around — whichever you read more comfortably.
Does it work for SRT and VTT?+
Both. The stacked lines are written as multi-line cue text, which is valid in SubRip (.srt) and WebVTT (.vtt). The file opens in any player that read the original.
Is it free, and do I need an account?+
You can create bilingual subtitles for free with no signup. Upload, translate, and download in the browser.