Back in the middle of February I shared an easy way to add a timer or stopwatch into a Google Slides presentation.
Another way you could embed a timer, stopwatch, date and time directly into your Slides presentation is to use the Slides Timer.
Embedded below is a 1 minute and 7 second YouTube tutorial followed by directions that information that was taken directly from the extension website.
Create timmers using placeholders. ie <<0:00+>>, <<5:00->>, <<time>>, <<date>>, <<shortdate>>, <<longdate>>
Slides Timer is an extension which will automatically bring timers to life in presented slides. Times placed between << and >> will be replaced with a timer. Use - as the last character to count down from the specified time. Use + to count up from the specified time. use <<time>> to display the current time.
<<5:00->> will count down starting at 5 minutes.
<<2:00+>> will count up starting at 2 minutes
<<time>> will display the current time
<<time^>> will display the current time without seconds
<<time&>> will display the current time without am/pm
<<time^&>> will display the current time without seconds and am/pm
<<date>> will display numeric dates in / format
<<shortdate>> will display abbreviated word date values
<<longdate>> will display full word date values
<<00:30-->> will advance to the previous slide on countdown
<<00:30-+>> will advance to the next slide on countdown
<<00:30-@>> will trigger inserted audio on countdown
<<00:30-!>> will trigger inserted video on countdown
<<00:30-~>> will continuously countdown when navigating slides.
<<00:30+~>> will continuously countup when navigating slides.