Ada is located at 34°46'27" North, 96°40'40" West (34.774444, -96.677778).
According to the United States Census Bureau, the city has a total area of 15.77 mi2 (40.85 km2). 15.70 mi2 (40.67 km2) of it is land and 0.07 mi2 (0.19 km2) of it is covered by water. The total area is 0.45% water.
Ada is located in the Central Standard Time (CST) timezone, GMT-06:00. It observes Daylight Saving Time (DST).