Parker is located at 39°31'6" North, 104°45'38" West (39.518611, -104.760833).
According to the United States Census Bureau, the town has a total area of 14.60 mi2 (37.82 km2). 14.59 mi2 (37.78 km2) of it is land and 0.02 mi2 (0.05 km2) of it is covered by water. The total area is 0.13% water.
Parker is located in the Mountain Standard Time (MST) timezone, GMT-07:00. It observes Daylight Saving Time (DST).