FurySync

This free software can be used to quickly synchronize all the lines of a subtitle No need to type in the time and the length of each subtitle like with Subtitle Workshop: with FurySync, which integrates a media player, you synchronize the beginning of a line by just clicking a button (or pressing F2) when you hear it on the video, and the end by clicking another button (or releasing F2).

If you are working on a subtitle which already has a timing (not a new one), what you could not synchonize with these actions will be automatically computed by the program. Thus, synchronizing a subtitle won't last more than the length of the video. This can be checked as FurySync also shows how much time you spent on the subtitle.