is gps speed accurate

GPS speed is generally quite accurate, often within a margin of 1 to 2 km/h. It calculates speed based on changes in position over time, so if your GPS signal is strong and uninterrupted, you’re golden. However, tall buildings, dense foliage, or tunnels can confuse your satellite signals and cause fluctuations. For most driving purposes, it’s more reliable than your car's speedometer, which can be affected by tyre wear and calibration quirks. Just don’t rely on it for drag racing or precision timing unless you’re feeling very lucky.