Why convert SRT to SUB?
MicroDVD .sub was common in the early-2000s DivX era and some older DVD-authoring tools and media players still require it. The key difference from .srt is that .sub stores timing as video frame numbers rather than clock timestamps, which is why the conversion requires the video's frame rate. Note that .sub is also used for VobSub image-based subtitles paired with a .idx file, which is a completely different format and not the target here.
How to convert SRT to SUB
Subtitle Edit FREE
Open the .srt in Subtitle Edit, go to File > Save As, select "MicroDVD" from the format dropdown, enter the video frame rate when prompted, and save the .sub file.
Gnome Subtitles FREE
Open the .srt in Gnome Subtitles, go to File > Save As, select MicroDVD, set the frame rate to match your video, and save.
Subtitle Workshop FREE
Open the .srt in Subtitle Workshop and use File > Save As to select the MicroDVD format, then enter the correct video frame rate.
Programs that convert SRT
About these formats
.SRT
SubRip Subtitle File
An SRT file (SubRip Subtitle) stores subtitles as plain text with timecodes. You don't open it alone - rename it to match your video file, keep both in the same folder, and VLC or MPV loads…
Open .SRT details →
.SUB
MicroDVD / SubViewer Subtitle File (text-based movie subtitles)
A SUB file stores movie subtitles as plain text, either in MicroDVD format (frame numbers in braces) or SubViewer format (timecodes). To use it, give it the same name as the video and put…
Open .SUB details →Quality & what to watch
- Frame rate must match your video exactly - a wrong value shifts all subtitle timing by a fixed percentage, making them consistently early or late.
- The
.subextension is shared by VobSub (image-based, paired with.idx) and MicroDVD (text-based); confirm which format your target player or tool expects. - SRT is better supported for modern use; switch to MicroDVD
.subonly when a specific older player or DVD-authoring tool requires it.
Frequently asked questions
Can I convert SRT to SUB online?
Will the subtitle text change during conversion?
What is the difference between MicroDVD .sub and VobSub .sub?
.sub is plain-text with frame-based timing; VobSub .sub is an image-based format extracted from DVD streams that must be paired with a .idx file - they are not interchangeable.
