Kernersville is located at 36°7'9" North, 80°4'26" West (36.119444, -80.073889).
According to the United States Census Bureau, the town has a total area of 12.17 mi2 (31.51 km2). 12.10 mi2 (31.33 km2) of it is land and 0.07 mi2 (0.18 km2) of it is covered by water. The total area is 0.57% water.
Kernersville is located in the Eastern Standard Time (EST) timezone, GMT-05:00. It observes Daylight Saving Time (DST).