This ghetto tool takes a SubRip .srt subtitle file or a WebVTT .vtt file and converts it into a simple .csv file compatible with Steinberg Nuendo's marker import -- handy for ADR sessions.
Simply select a .srt/.vtt file below, choose the correct framerate for SMPTE timecode conversion (SRT/VTT timestamps are based on clock time, without frames) and click Upload.
Privacy notice: The uploaded subtitle file is converted in memory with the CSV being generated on-the-fly, both of which go away as soon as your browser downloads the result; they are otherwise not stored anywhere on this server. I don't really want or care about your subtitle files.