There are several tools to convert times.
Utilities
The utilities tool offers several functions to convert times. They are located in the Time tab.
•Change frame rate
This utility changes the frame rate of the project.
It does not modify the times of the subtitles.
•Time stretch - First and last
It allows to specify the new time-ins for the first and last subtitles in the track. All subtitles in between will be stretched accordingly too.
It does not change the frame rate of the project, it only modifies the subtitles's times.
•Time stretch - Numeric
It allows to specify the factor to multiply the times, and optional offsets.
It does not change the frame rate of the project, it only modifies the subtitles's times.
•Time stretch - Source frame rate
This utillity modifies the times of the subtitles. It allows to specify the source or target frame rate.
It does not change the frame rate of the project, it only modifies the subtitles's times.
•Time stretch - Source frame rates
This utillity works in the same way as the one above. But it allows to select both source and target frame rates.
Time conversion dialog
The time conversion dialog allows to convert times between different frame rates, and using a visual feedback.