The short answer
SRT stands for SubRip Subtitle, named after the SubRip program that extracted subtitles from video. A .srt file contains only text: the words to show and when to show them. It contains no video and no audio, which is why it is small and easy to edit.
Structure of an SRT entry
1 00:00:01,000 --> 00:00:04,000 This is the first subtitle. 2 00:00:04,500 --> 00:00:07,000 This one has two lines.
- Number – the cue's position, starting at 1.
- Time range – start and end in
hours:minutes:seconds,milliseconds, separated by-->. Note the comma before the milliseconds. - Text – one or more lines. Simple tags like <i>italic</i> are widely supported.
- Blank line – marks the end of the entry.
How to open an SRT file
Any text editor (Notepad, TextEdit in plain-text mode, VS Code) can open and edit it. Save it with UTF-8 encoding so accented and non-Latin characters display correctly. Media players such as VLC load a .srt automatically when it has the same file name as the video.
Common problems
- Using a dot instead of a comma in timestamps (that is the WebVTT style).
- Missing blank line between entries, so two cues merge.
- Wrong encoding, which shows garbled characters.
- Overlapping times, where one cue ends after the next begins.
How to create one
The quickest way is to write your text with one subtitle per line and run it through the TXT to SRT converter, then adjust timings in your editor. If you need the web format, convert with SRT to VTT.
Frequently asked questions
Is an SRT file the same as closed captions?
An SRT file can hold either subtitles or captions. Captions usually also describe sounds, such as [music].
Can an SRT file contain several languages?
Usually one file holds one language; you create a separate .srt for each language.