Exact time
Measuring your connection…
Setting a watch to the second
Mechanical watch with hacking seconds
Pull the crown out when the seconds hand reaches 12; the hand stops. Set the minute hand a minute ahead of the time shown here. Push the crown in on the long pip, or when the clock above flashes at :00.
Quartz watch
Most quartz movements restart their second at the moment you push the crown in. Set the minute ahead, wait for :00, and push in. Expect to land within a quarter of a second with practice.
Watch without hacking
Note how many seconds it runs ahead or behind using full screen mode, then set the minute hand so the error splits evenly. Check again after 24 hours to measure its daily rate.