Text to SRT
Paste the script you read and how long the recording is. Each caption gets time in proportion to its length, which lines up well for steady narration; check it once against the audio and nudge it with the SRT fixer if needed. Nothing leaves your browser.
0 captions over 30.0 s
Your subtitles
Line length for short videos
On a phone, 25 to 35 characters per line and one or two lines per caption is easy to read. TV subtitles use up to 42. With no length given, the tool assumes a normal reading pace of 150 words a minute.