How to merge srt, idx or sub subtitles with an MKV video in seconds

This tutorial will show you step by step how to merge (combine) SRT, IDX, and SUB subtitles with an MKV video file in just a few seconds.

You can also merge multiple subtitle files with an MKV video file.

How to merge subtitles with MKV movies using MKVToolNix

MKVToolNix is a set of free tools to create, split, edit, mux, demux, merge, extract, and inspect MKV video files.

It's available for Windows, macOS, and Linux.

You can install this tool on your computer, or you can use the portable version.

You can download MKVToolNix here (official website).

The following steps will show you how to permanently embed (hardcode) the subtitles into your MKV movie.

1. Make sure that the subtitle file is in the same folder as the MKV video file.

2. Make sure that the subtitle file has the same filename as the MKV video file.

Example:

  • Movie.mkv
  • Movie.srt
  • Movie.sub
  • Movie.idx

3. Open MKVToolNix.

4. Click on the + Add source files button located at the bottom.

MKVToolNix Add source files button

A “Add media files” window will appear.

5. Go to the location on your computer where the MKV video and subtitle file(s) are stored.

6. Select the MKV video file and subtitle file(s) (.srt, .sub or .idx).

7. Click on the Open button.

Open MKV File and Subtitle File in MKVToolNix

8. In the Destination file section (located at the bottom), you can view and change the location on your computer where MKVToolNix will save the new MKV video file.

MKVToolNix Destination file section

You can change the location by clicking on the MKVToolNix change location of destination file button (folder) button located next to the “Destination file” field.

9. When you're ready, you click on the Start multiplexing button located at the bottom.

MKVToolNix Start multiplexing button

MKVToolNix will now merge the SRT or IDX or SUB subtitles with the MKV video file in a few seconds.


Maybe you're also interested in:

How to merge srt subtitles with an MP4 video

How to merge srt subtitles with an AVI video

How to remove hardcoded subtitles from MKV video files