taximeter

A taximeter is a device installed in taxicabs to automatically calculate fares based on distance traveled and time elapsed. It measures the vehicle’s movement and applies a local tariff to determine the charge. The meter typically displays the fare in real time and can print a receipt. In addition to a base fare, it may apply per-kilometer rates, waiting-time charges, surcharges, and minimum fares.

Taximeters were developed in the late 19th century, with mechanical models giving way to electronic and digital versions in the late 20th century. They have been widely deployed worldwide, with regional variations in tariff structures and regulatory requirements. Advances include GPS-enabled meters and integrated dispatch features.

Operation: The meter uses a speed or distance sensor (often driven by the vehicle’s wheel or prop shaft) or GPS to determine distance. Time is tracked to measure waiting time. The tariff table sets rate values; the meter multiplies distance by the per-unit rate and adds waiting-time charges. It updates the fare continuously and typically prints a receipt at trip end. Many meters include tamper-evident seals and require periodic calibration.

Types: Mechanical meters use gears and prisms, while electronic meters rely on microprocessors. Modern meters are digital, often GPS-based or connected to fleet telematics; some are integrated with on-board computers or mobile apps. They may offer multiple fare options, city-specific tariffs, and passenger displays.

Regulation: Taximeters are subject to regulatory certification, calibration, and seal inspections in many jurisdictions to ensure accuracy and fairness. Tampering is illegal in most places. Data handling and privacy considerations may apply where meters transmit trip data to central systems.