Glossary
What Is an SRT File? Format Definition Explained
An SRT file is a plain-text subtitle file format that contains timed captions — the most widely supported subtitle format on the web.
Definition
An SRT (SubRip Subtitle) file is a plain-text subtitle file format that lists captions with start and end timecodes, used universally across video players and platforms.
Also known as: SubRip, .srt
Full Explanation
An SRT file is the most common subtitle file format on the web. It is a plain-text file with the extension .srt, containing a sequence of caption entries. Each entry consists of: an index number, a start and end timecode in HH:MM:SS,mmm format separated by '-->', and one or more lines of caption text, followed by a blank line. SRT files were originally created for the SubRip software in the early 2000s and have since become a universal standard, supported by YouTube, Netflix, VLC, Premiere Pro, and virtually every video tool. SRT files do not support styling, positioning, or formatting — they are pure timed text. For richer features, use the VTT format. To embed SRT captions permanently into a video, you need to burn them in via a caption tool or video editor.
Examples
- -1\n00:00:01,000 --> 00:00:03,500\nWelcome to the show.\n\n2\n00:00:04,000 --> 00:00:06,000\nLet's get started.
Related Terms
Frequently Asked Questions
Everything you need to know before you start.
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Any text editor (Notepad, VS Code, TextEdit) can open an SRT file. To use it with video, drop it into a video player like VLC or upload it alongside your video to platforms like YouTube.