Approximately 14,000 km/hour
But GPS signals travel at the speed of light and the satellites transmit in a repeating, synchronized sequence due to the accuracy of the built-in atomic clocks which account for how accurate each satellite is at tracking time. Image courtesy of commons.wikimedia.org.  GPS satellites orbit at a height of about 12,000 miles (19,300 km) and orbit the earth once every 12 hours. About 24 GPS satellites orbit the earth every 12 hours. These satellites are traveling around the earth at speeds of about 7,000 mph (11,200 kph). GPS satellites are powered by solar energy. They have backup batteries onboard to keep them running in the event of a solar eclipse, when there's no solar power. If the geostationary satellites were moving, they would have to move at a speed of about 7,000 mph to maintain a stationary orbit above a fixed point on the earth. That is about the same speed as the GPS satellites that orbit the earth twice a day. To maintain orbit a satellite must travel at a speed of about  18,000 miles per hour to remain in orbit. Too much speed and the  orbit is broken and the craft will go into s … pace. Very easily. The GPS receiver measures how long it takes a certain   radio signal to travel from the GPS satellite(s) to itself, and from   that, the receiver calcu … lates the distance. It can do that because it   knows precisely how fast the radio signal travels. Making the world better, one answer at a time. The GPS satellite moves with the speed of 7000 km/hour and completes one orbit around the Earth at an altitude of 20,200 km in about 12 hours. Very easily. The GPS receiver measures how long it takes a certain   radio signal to travel from the GPS satellite(s) to itself, and from   that, the receiver calcu … lates the distance. It can do that because it   knows precisely how fast the radio signal travels. Satellites in low earth orbit (which is generally considered from about 100 miles to 621 miles above the earth's surface) do orbit the earth about once every 90 minutes for an average speed of 17500 mph. low earth orbit satellites orbit the earth in roughly 90 minute to 1.5 hour periods. This means that they are fast moving at17,000mph middle earth-Most of the satellites in this orbital altitude circle the earth at approximately 6,000 to 12,000 miles above the earth in an elliptical orbit around the poles of the earth. Velocity of GPS Satellites. Global Positioning System (GPS) satellites travel approximately 14,000 km/hour, relative to the Earth as a whole, as opposed to relative to a fixed point on its surface. The six orbits are tipped at 55° from the equator, with four satellites per orbit (see diagram). Velocity Relative to the Earth. Relative to the Earth, GPS satellites orbit twice in a sidereal day, the length of time the stars (instead of the sun) take to return to the original position in the sky. Since a sidereal day is about 4 minutes shorter than a solar day, a GPS satellite orbits once every 11 hours and 58 minutes. With the Earth rotating once every 24 hours, a GPS satellite catches up to a point above the Earth approximately once a day Each satellite in the GPS constellation orbits at an altitude of about 20,000 km from the ground, and has an orbital speed of about 14,000 km/hour (the orbital period is roughly 12 hours-contrary to popular belief, GPS satellites are not in geosynchronous or geostationary orbits).  Some satellites revolve around the earth in elliptical orbits. These satellites move rapidly when they are near perigee, or their lowest altitude; they move slowly when they are near apogee, or their highest altitude. A satellite in low earth orbit circles the earth 100 to 300 miles above the earth's surface. Because it is close to the earth, it must travel very fast to avoid being pulled out of orbit by gravity and crashing into the earth. Satellites in low earth orbit travel about 17,500 miles per hour. The satellite is moving much faster than the earth's surface, though, because it must cover much more distance in the same amount of time. A geosynchronous satellite is moving at about 3.07 km/sec. Lower orbits are much faster. Satellites orbiting the Earth such as the Space Shuttle make one orbit every 90 minutes and cover a circumference of about 40,000 kilometers. This works out to about 445 kilometers per minute or 26,000 kilometers/hour which is 17,000 miles per hour. 
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how fast do gps satellites travel