Script to SRT
Turns your text into timed SRT captions
SRT Output
Paste your script, set the video duration and words per caption, then click "Generate SRT".
This free automatic subtitle generator turns your script or transcript into a timed SRT file. Paste the text, set the video duration and how many words each caption holds, and the tool splits it into numbered subtitle lines with start and end times. It suits creators, educators and marketers. It runs in your browser, needs no sign-up and does not listen to audio.
Turns your text into timed SRT captions
Paste your script, set the video duration and words per caption, then click "Generate SRT".
Paste a script or transcript and get correctly formatted SRT blocks with counters, timecodes and caption text.
Control caption length so each subtitle stays short enough to read before it disappears.
The tool spreads your video duration across the captions, giving every line a start and end time.
Copy the SRT text or download it as an .srt file ready for YouTube, video editors and players.
Three steps from a blank form to a result you can use.
Add the exact words spoken in your video, from a script, a transcript or your own notes typed out in full.
Enter the video duration and the number of words per caption you want.
The tool splits the text into numbered captions with timecodes. Copy it or download the .srt file, then fine-tune timing in your editor.
An SRT file is a plain text file of numbered captions with start and end times. This tool builds one from text you already have, which is far faster than typing timecodes by hand.
SRT, short for SubRip Text, is the most common subtitle format online and is supported by most video platforms and editors. Each caption is a block with four parts:
1
00:00:00,000 --> 00:00:03,600
Welcome back to the channel.
Today we plan a whole week of meals.
2
00:00:03,600 --> 00:00:07,200
You only need one hour on Sunday
and a list you can reuse.The file uses the .srt extension. There is no official text encoding, but saving as UTF-8 is the safe choice, since some platforms such as YouTube only accept UTF-8. Some players read simple tags such as <i> for italics, but support varies, so we suggest keeping captions plain.
Captions are only useful if people can read them in time. Professional subtitle guides give clear limits. Netflix's English timed text style guide, for example, sets these rules:
| Rule | Limit |
|---|---|
| Characters per line | 42 |
| Lines per caption | Maximum two, and one line when the text fits |
| Reading speed, adult programs | Up to 20 characters per second |
| Reading speed, children's programs | Up to 17 characters per second |
| Minimum caption duration | 20 frames, about 4/5 of a second |
Two lines of 42 characters hold roughly 12 to 15 everyday English words, so we suggest a Words per Caption setting between 7 and 12 for most videos. Fast talkers need fewer words per caption, and slow, careful narration can take more.
To check reading speed, divide the characters in a caption by its duration in seconds. If the result is above 20, use fewer words per caption or give the video more time.
Example: a creator has a 60 second recipe video and a 150 word script. These numbers are an illustration of how the settings interact.
A 10 word caption is usually around 55 to 60 characters. At 4 seconds, that is about 14 to 15 characters per second, comfortably under the 20 per second limit. The first caption runs from 00:00:00,000 to 00:00:04,000, the second from 00:00:04,000 to 00:00:08,000, and so on.
The creator imports the file into their editor, plays it back and moves two captions that start before the speaker reaches those words. Because the timing comes from even spacing, small fixes like this are normal.
For teams producing videos on a schedule, Onethread can track each step, from script and edit to captions and publishing, with an owner and due date.
Remove speaker names, notes and timestamps from your script before pasting, unless you want them on screen.
Enter only the spoken length as the duration if your video opens or ends with music or silence.
Keep captions at or under 20 characters per second so viewers can read them comfortably.
Save and upload the file as UTF-8 to avoid broken accents and symbols on YouTube and other platforms.
Play the full video with captions on before publishing and fix any line that appears early or late.
No. It does not listen to audio or video. It takes a script or transcript you paste and splits it into timed SRT captions. If you only have the recording, create a transcript first with a transcription tool or your platform's auto captions, then paste that text here to build a clean SRT file.
It spreads the video duration you enter across the captions it creates from your text, so each caption gets a start and end time. The timing is an even estimate, not matched to the exact moment words are spoken. Expect to nudge some captions in your video editor, especially around pauses or music.
SRT is a plain text subtitle format. Each caption has a number, a timecode line with start and end times in hours:minutes:seconds,milliseconds, one or more lines of text and a blank line. It uses the .srt extension and works with most video platforms, editors and media players.
For most videos, 7 to 12 words per caption works well. Subtitle guides such as Netflix's limit captions to two lines of 42 characters and a reading speed of about 20 characters per second for adults. Use fewer words for fast speech and children's content, and more for slow narration.
Yes. YouTube accepts SRT subtitle files. Save the file as UTF-8, since YouTube only supports that encoding for SRT, then upload it through the subtitle settings for your video. Preview the captions after upload and adjust any timing that does not match the speech.
Yes. It is free and needs no sign-up. The splitting and timing run in your browser, so your script is not uploaded or stored. You can generate as many SRT files as you need and regenerate with a different words per caption setting until the captions read well.