This script replaces the original Level Duration script. Unlike the previous one, this script fetches your level unlock date from the API, so it is much more accurate. To do this it relies on WKOF, so you will need to install that first for this to work.
There are a couple of different display options for this script. If you have been on your current for say 4 days and 2 hours, you can choose from these options:
4 days 2 hours 4.1 days on level 4.1 days 4d 2h 4日2時 4日2時 (in the FangSong font)