Dual-language · file, not extension

Bilingual subtitle generator

A bilingual subtitle generator makes one file that shows two languages at once — the original line and its translation stacked under a single timecode — so you can study a language while you watch. Unlike a browser extension that only overlays subtitles on Netflix or YouTube in a tab, SubLingo gives you a downloadable .srt, .vtt, or .ass file that plays offline in VLC, mpv, Plex, or Infuse. Upload a file, pick the second language from 100+ options, choose which language sits on top, and download — timecodes stay frame-accurate because only the text is translated.

Last updated: 2026-06-11

subtitle-translator

Drop your subtitle file here, or click to browse

Supports .srt, .vtt, and .ass / .ssa

No file handy?
Order:
Timecodes preservedBilingual outputSRT, VTT & ASS100+ languagesNo signup to try

How to make dual-language subtitles

01

Upload a subtitle file

Drop in your .srt, .vtt, or .ass file. SubLingo parses every cue and locks the timings in place.

02

Pick the second language

Choose the translation language from 100+ options and set which language sits on top.

03

Generate bilingual

Bilingual mode is on by default here. SubLingo translates the text and stacks both lines under one timecode.

04

Download & watch offline

Download the dual-language file and load it in VLC, mpv, Plex, or any player — no extension needed.

A file you keep, not an overlay you rent

Most dual-subtitle tools are browser extensions: they show two languages only while a supported streaming site plays in a tab, and they stop the moment you close it. A bilingual subtitle file is different — it is yours to keep, share, and play on any device. Use it on your own downloads, DVDs ripped to .mkv, anime, or offline copies, in VLC and mpv on a laptop or Plex and Infuse on a TV. Learners who rewatch the same episodes build a small library of dual-language files instead of re-running an extension each time. See the full bilingual subtitles guide for player-by-player setup.

Keep lines within reading speed

Two stacked lines take longer to read than one, so dual subtitles work best when each language stays short. Reading-speed and line-length limits vary a lot by language — English allows about 20 characters per second and 42 per line, but Japanese just 4 and 13. Check the subtitle limits by language table when you pick your pair.

Bilingual subtitle questions

What is a bilingual (dual-language) subtitle file?+

It is a single subtitle file that shows two languages at the same time — the original line and its translation stacked under one timecode. When you play the video, both appear together, so you can read the target language and check the meaning without pausing or switching subtitle tracks. SubLingo writes both lines into one .srt, .vtt, or .ass file you can keep and reuse.

How is this different from a browser extension like Immersive Translate or Trancy?+

Browser extensions overlay dual subtitles only while you watch in a tab, on sites they support such as Netflix or YouTube. SubLingo instead generates a portable subtitle file. It works offline in any player — VLC, mpv, Plex, Infuse, or a TV app — on your own video files, downloads, or anime, and keeps working after you close the browser. No extension and no streaming-site dependency.

How do I make dual subtitles for VLC, mpv, or Plex?+

Upload your subtitle file, pick the second language, choose which language sits on top, and download the bilingual file. Name it to match your video (movie.mkv → movie.srt) and drop it in the same folder, or load it manually from the subtitle menu. Because it is an ordinary subtitle file, every offline player reads it without setup.

Which language goes on top — original or translation?+

You choose. Learners usually put the target language (the one being studied) on top and their native language below, so the eye reads the new language first and uses the translation only to confirm meaning. SubLingo lets you flip the order before downloading, and both lines share the exact same timecode.

Does it work with anime .ass files and keep the styling?+

Yes. For .ass and .ssa files the styles, positioning, and override tags are preserved — only the dialogue text is translated and stacked with the original. This suits fansub and immersion-learning files (for example from Kitsunekko) that you watch in mpv or Plex rather than in a browser.

Will the timecodes stay in sync?+

Yes. SubLingo parses the file into timed cues and translates only the text, so every start and end time is unchanged. The original line and the translation share one timecode, and the file drops back onto your video frame-accurate.

Is the bilingual subtitle generator free?+

Yes — free, with no account and no signup. Upload a subtitle file, generate the dual-language version, and download it in your browser. There is no per-file size cap, so full-length films and full anime episodes work.