What I use on my Mac now is Timerik, a very handy, very Mac-like, very affordable timer app that shows attention to detail and usability not available in many Mac timer apps. Tera Talks, March 29, 2017
No need for words, just look at this small window that's created specifically for last macOS and contains features which should be in all macOS apps. We believe that Timerik is most beautiful counter in Mac App Store!
Timerik is really small and comfortable to use tool. But if you click the settings button you will see various parameters to set the counter for best usage.
Click on the book icon brings you a window where you can add, edit and delete AppleScripts files of actions.
If you not really good in scripting, we add quick installation for next scripts: Shutdown, Sleep, Restart, Log out and Stop music.
Need to set up several notifications? Just click the plus icon at the bottom and use an additional window as you wish!
For each counter you will see the counter's assistant at the status bar. Action icons lets you to know which counter when will be run.