I use an older Windows app called Subtitle Processor 7.7.1, which doesn't seem to have been updated since 2009 or so but still works fine for me. I looked very briefly at SubtitleEdit which was mentioned in this thread to see if it is better, but Subtitle Processor seems to me to have more comprehensive subtitle adjustment abilities than SubTitleEdit, though I could be mistaken. Source: almost 2 years ago

There may be better places, since I've just stuck to the same one for years now (and don't need them often enough to look into alternatives), but I usually use either subscene or opensubtitles. There are also programs that can automate it like bazarr, but it requires you to also use Sonarr/Radarr. Source: 11 months ago

Have you checked these ones? Https://subscene.com/ Https://subdl.com/. Source: 12 months ago

Could check sites like opensubtitles.org or subscene.com, where users can upload subtitles. Source: 12 months ago

Use https://subscene.com/ and they are in srt format which is what every media player uses. Source: 12 months ago

Https://subscene.com seems pretty good. Source: about 1 year ago