How to Create an SRT File from Plain Text
You have a transcript or script but need a properly formatted SRT file. Maybe you transcribed audio manually, received a text document from a translator, or wrote captions from scratch. Creating an SRT requires adding sequence numbers, timestamps, and proper block structure. Here is how to do it correctly without specialized software.
By CapsAI · Updated 19 August 2026
Key takeaways
- Each SRT block needs a sequence number, a timestamp line with start and end times, and the caption text.
- Keep each subtitle to 1-2 lines, with each line under 42 characters.
- Timestamps must be in HH:MM:SS,mmm format with a comma before milliseconds.
- For large files, auto-sync tools like CapsAI save hours compared to manual timestamp entry.
The anatomy of an SRT file
An SRT file is plain text with a repeating four-part structure: (1) a sequence number starting at 1, (2) a timestamp line showing start --> end times, (3) one or two lines of caption text, and (4) a blank line separating it from the next block. Nothing else. No header, no metadata, no special encoding declaration.
A minimal example looks like this: Line 1 is '1', line 2 is '00:00:01,000 --> 00:00:04,000', line 3 is 'Welcome to this video', and line 4 is blank. Then block 2 starts with '2' on the next line. This simplicity is why SRT remains the most widely supported subtitle format across platforms and editors.
- Sequence numbers start at 1 and increment by 1.
- Timestamp format: HH:MM:SS,mmm --> HH:MM:SS,mmm (note the comma, not dot).
- The arrow is exactly: space, dash, dash, greater-than, space.
- Text lines should not exceed 42 characters each.
- Each block ends with exactly one blank line.
Splitting your text into subtitle-sized segments
Take your plain text and divide it into chunks that a viewer can read in 1-5 seconds. A comfortable reading speed for captions is about 15-20 characters per second. So a 3-second subtitle should contain roughly 45-60 characters maximum, split across 1-2 lines if needed.
For Hindi text, character counting is slightly different because Devanagari conjuncts render as single visual units but may be multiple Unicode code points. Count by visual characters (aksharas) rather than bytes. A 3-second Hindi caption should contain roughly 25-35 aksharas for comfortable reading, which accounts for the slightly slower reading speed of dense Devanagari text.
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Adding timestamps manually
Play the video and note when each phrase starts and ends. Record times in HH:MM:SS,mmm format. You can use VLC's time display (enable milliseconds in preferences) or any media player that shows precise timestamps. Round to the nearest 100ms if exact millisecond precision is difficult to capture by ear.
Leave a small gap (80-200ms) between consecutive subtitles. This gap gives the viewer's brain a moment to recognize that new text has appeared. Without a gap, consecutive subtitles with similar lengths can blend together visually, especially at fast speaking rates common in Indian content creators' videos.
Automated alternatives for large files
Manually timing a full video is practical for short clips (under 2 minutes) but becomes extremely time-consuming for longer content. A 10-minute video might have 150-200 subtitle entries. For these cases, use CapsAI's script-to-subtitle feature: paste your pre-written text, upload the video, and the tool aligns your words to the audio automatically.
This hybrid approach gives you the quality of human-written text with the precision of automated timing. It is particularly valuable for Indian creators who write scripts in Hindi or other regional languages before recording - you already have the text, you just need it synced to your delivery.
Frequently asked questions
Can I create an SRT with just a text editor like Notepad?
Yes. SRT is plain text. Open Notepad (or any text editor), write your blocks in the correct format, and save with a .srt extension and UTF-8 encoding. No special software is required.
What happens if my timestamps overlap?
Most players will display both subtitles simultaneously during the overlap, which looks messy. Ensure each subtitle's end time is earlier than or equal to the next subtitle's start time. A small gap between them is even better.
How do I handle Hindi text that mixes with English in the same subtitle?
Write the mixed text naturally on one or two lines. SRT supports any Unicode text. The Devanagari and Latin characters coexist without special markup. Just ensure the file is saved as UTF-8 so both scripts are preserved correctly.
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