How average speed cameras work
An average-speed zone divides the zone length by the time you take, and fines you if that average is over the limit; slowing down only at the cameras does not help. For example, a 3 km zone with a 70 km/h limit needs at least 2 minutes 34 seconds.
How it is calculated
Cameras at the start and end read your number plate and record the time. Average speed = zone length ÷ (end time − start time). If the average is over the limit you are fined, no matter where you sped up or slowed down.
| Zone length | Limit | Minimum time |
|---|---|---|
| 3 km | 70 km/h | 2 min 34 s |
| 5 km | 90 km/h | 3 min 20 s |
| 10 km | 100 km/h | 6 min 00 s |
Common myths
- "Just slow down at the camera": no, it is the average over the whole zone.
- "If my average is fine, I can't be caught": zones often contain ordinary speed cameras too.
- "Zones are short": they range from under 1 km to over 10 km, often in tunnels and on expressways.
Average-speed zones in ZeroCyl's data
ZeroCyl currently lists 75 zones in Taiwan, plus zones in South Korea with their real start and end points. Locations by region:
How ZeroCyl helps
- A spoken alert when you enter a zone, with the limit and the length.
- Your average speed, distance driven and distance left, live on screen.
- The average to keep for the rest of the zone so you stay under the limit.
- A warning when your average is over the limit, and a note when it is back under.
FAQ
What is the fine for speeding in an average-speed zone?
The same as for ordinary speeding, based on how far your average is over the limit. A zone can also contain ordinary speed cameras that catch your speed at that point.
Can I stop inside a zone to lower my average?
Stopping lowers your average, but stopping on a shoulder, in a tunnel or on an expressway is illegal and dangerous. Just keep to the limit.
How does ZeroCyl know I entered a zone?
When you pass near the start, ZeroCyl announces the zone, then adds up distance and time from GPS to show your average. It ends after the zone length, when you turn off the road, or after stopping for 3 minutes.