Surveyors use GPS (Global Positioning System) as it offers an incredible cost saving by drastically reducing setup time at the survey site. In public transportation the use of taxi continuously increasing and accordingly the need for the exact fare calculation is also increasing. Mileage meters for commercial vehicles such as taxicabs and long- haul trucks are calibrated and certified by governmental agencies for a specific tire pressure and a certain rim size. When the tire pressure and rim size of a vehicle are changed, distance errors of 3 percent can be obtained. For consumers, increased mileage readings by a taximeter increase their costs. For a state governmental agency which taxes a long- haul truck based on the number of miles driven by the long-haul truck within the state, shortened mileage readings result in significant revenue shortfall for the state. Consequently, a need exists for a technique of calibrating mileage meters, such as taximeters and long-haul truck mileage meters. Using the advantage of GPS system to fulfill the need of exact taxi fare calculation, I have developed GPS based taxi fare system.