Keep it simple!
I use an analogue quartz watch that lives in my work room for regulating watches, write down the result every few hrs and calculate the rate in secs per day. That’s quicker and easier than going to the computer and looking at Time Is. The quartz watch gains 1 sec/ week, in the context of timing iver a 24 hr period that’s negligible.
Accurate time sources are everywhere thesedays, hard to envisage what things were like prior to the 70s when quartz watches became popular. I remember the mantle clock being set against the time pips on the radio!