How to adjust subtitle durations
Add your file
Choose the SRT or VTT file with durations that are too short or too long.
Choose a mode
Pick one mode, for example Set from reading speed, and fill in its fields. Start times stay as they are.
Download
Click Adjust durations, then click Download. A subtitle never grows into the next one: it stops 80 ms before it.
When to use Adjust durations
- Viewers say the subtitles disappear before they can read them.
- Your style guide asks for a minimum of 20 frames at 24 fps, which is 0.833 seconds.
- A long pause left some subtitles on screen for 10 seconds or more.
- A QC report flags a reading speed above 17 characters per second.
- Automatic captions flash by and need more time on screen.
- You timed the subtitles tightly to the speech and want each one to stay a little longer.
More free subtitle tools
Timing
Convert
Join and split
Clean up
Common questions
How do I make subtitles stay on screen longer?
Choose Add or remove seconds and type a positive number. You can also choose Set from reading speed. Start times do not change.
What is the minimum duration for a subtitle?
Netflix asks for at least 5/6 of a second, which is 20 frames at 24 fps. The tool starts with 0.833 seconds as the minimum and 7 seconds as the maximum.
What reading speed should I choose?
Many style guides use 17 to 20 characters per second. The tool starts at 17, which is comfortable to read.
Can a longer subtitle run into the next one?
No. The end of a subtitle stops 80 milliseconds before the next subtitle starts. If the next subtitle is too close, the subtitle keeps its old end.
Does the tool change start times?
No. Only end times change. To move start times, use the subtitle shifter.
How do I shorten subtitles that stay too long?
Choose Minimum and maximum and set a Maximum, for example 7 seconds. Every longer subtitle ends sooner.
Is my file uploaded?
No. The tool runs in your browser. Your subtitle file never leaves your computer.
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