What Is an SRT File?
An SRT (SubRip Subtitle) file is a plain-text file that stores subtitles with timecodes, used to add closed captions to videos across platforms.
An SRT file — short for SubRip Subtitle — is a plain-text file that stores a video’s subtitles along with the exact timecodes for when each line should appear and disappear. It’s one of the most widely supported caption formats on the web.
What’s inside an SRT file
Each subtitle entry has three parts: a sequence number, a start-and-end timestamp, and the caption text. Players and platforms read these timecodes to display each line in sync with the audio. Because it’s just text, an SRT is tiny, easy to edit, and accepted almost everywhere — YouTube, Facebook, LinkedIn, Vimeo, and more.
SRT vs. burned-in captions
There are two ways to caption a video:
- SRT (closed captions) — a separate file the viewer can toggle on or off. Great for accessibility and SEO, since platforms can read the text.
- Open captions — text burned permanently into the video, always visible. Ideal for feeds where most people watch on mute.
Many creators use both: an SRT for platforms that support it, and burned-in captions for short-form clips.
Generating captions automatically
Typing out timed captions by hand is slow. quso.ai’s AI caption generator transcribes your video automatically, lets you edit the text, and can export an SRT or burn animated captions directly onto your clips — covering both formats from one workflow. Accurate captions boost accessibility, watch time, and reach.
Need subtitles in another language? quso.ai’s AI subtitle generator auto-transcribes your video and exports a ready-to-use SRT in 100+ languages.