Bilingual Subtitles
Make one subtitle file that shows two languages at the same time, from two files for the same video. Your files are processed in your browser.
Drop subtitle files here
SRT, VTT, ASS, SSA, SBV, or TXT files. Up to 50 at once.
Your files are processed in your browser and are not uploaded to our servers.
Preview on your video (optional)
Choose a video from your device. Video and captions stay in this tab. MP4 (H.264) or WebM usually works; MKV and other codecs may not play in your browser.
Create the bilingual file first, then play it here with your video.
What this tool does
This tool combines two subtitle files of the same video, in two languages, into one bilingual file. Each line of the second language is paired with the main line it overlaps most. You can save SRT with both languages in one subtitle, ASS with one language at the top and one at the bottom, or WebVTT.
How to make bilingual subtitles
- Select Choose files and add two subtitle files for the same video, or use Paste text for each one.
- Check the order: the first file is the main language. Use the arrows to swap the files.
- Choose the Output format and where the Second language goes.
- Select Create bilingual subtitles. The result shows how many lines were paired.
- Optional: open Preview on your video (optional) to play the result over your own video.
- Select Download to save the file.
Options explained
- Second language goes above the main line by default, or below it. The main language stays at the bottom.
- Italicize the second language is on. Second language color adds a color: a font tag in SRT, the style color in ASS. WebVTT has no color here.
- Minimum overlap to pair lines (%) defaults to 50% of the shorter line. One main line can collect several short second-language lines.
- Keep unpaired second-language lines is on, so no text is lost.
- ASS output has two styles, Primary and Secondary. Secondary is 25% smaller. The file is saved as UTF-8 with the main file’s name plus “.bilingual”.
Example
The main language and the second language (with Italicize the second language turned on):
1
00:00:01,000 --> 00:00:03,500
Where is the station?
1
00:00:01,100 --> 00:00:03,400
¿Dónde está la estación?
Output:
1
00:00:01,000 --> 00:00:03,500
<i>¿Dónde está la estación?</i>
Where is the station?
Format notes and limits
- Reads SRT, VTT, ASS, SSA, SBV and TXT with times. Styling inside lines is kept, such as italics. ASS drawings and comment lines are left out.
- Exactly two files per run, 20 MB per file.
- Players show a lot of text with two languages. To shorten long lines, use Subtitle line breaker on each file first. To join parts of a movie in one language, use Merge subtitles.
Questions
How are the lines of the two languages matched?
By time. A second-language line joins the main line it overlaps most, if the overlap covers at least 50% of the shorter line. You can lower this share when lines are not paired.
Which times does the new file use?
The times of the main language, the first file in the list. Second-language lines that pair with nothing keep their own times.
Is any text lost?
No. Every main line is kept, and with Keep unpaired second-language lines turned on, every second-language line appears once. Turn it off to drop lines that pair with nothing.
Which output format should I choose?
SRT works in almost every player. ASS gives the second language its own smaller style and color, for VLC, mpv and video editors. WebVTT is for web players; it makes two subtitles at the same time on different lines.
My two files are out of sync. What can I do?
Sync the second file first with Sync subtitles or Shift subtitles, then combine. Lines that are far apart in time cannot be paired.
Are my files uploaded?
Your files are processed in your browser and are not uploaded to our servers.
Last updated October 28, 2026 · Files never leave your browser.