About this tool
How quickly does your car really get from 0 to 100 km/h? The acceleration timer uses your smartphone’s GPS: it waits until you stand still, starts timing when you pull away and stops at the target speed. Besides 0–100 km/h it measures 0–50, 0–130 and the 80–120 km/h overtaking sprint, each with the distance covered.
Phones usually deliver a GPS position only once per second. To keep the time accurate anyway, the timer interpolates between two fixes back to the moment you started and reached the target speed. Everything runs in your browser; your location never leaves the device.
How it works
- Choose the run, e.g. 0–100 km/h, and tap “Start GPS”.
- Wait for a GPS fix and come to a stop. As soon as “Ready” appears you can accelerate.
- The time stops automatically at the target speed. Tap “New run” to measure again.
Frequently asked questions
How accurate is it?
With good GPS reception under open sky the deviation is usually a few tenths of a second. Tunnels, tall buildings and trees degrade the signal. Several runs in both directions even out slopes and wind.
Why do my times differ from the manufacturer’s?
Manufacturers measure under ideal conditions, often with only the driver, a full battery or the best temperature. Load, tires, slopes and weather add time. Many timing devices also subtract the first centimeters of rollout – this timer does not.
Do I need an app?
No, the timer runs in your browser. It needs a device that delivers the GPS speed in addition to the position – practically all smartphones do. Your current speed, distance and coordinates are shown by the GPS Speedometer.
Where may I measure?
Only where it is safe and allowed, e.g. on closed tracks. Follow traffic rules and never operate the phone while driving. How long the braking distance from high speeds is, is shown by the Stopping Distance Calculator calculator.