About

This site has tools to help GRTC riders track the frequency and reliability of buses.

All statistics are based on real-time arrival data from GRTC. New arrival data for buses is recorded every 20 seconds. That data is processed every few minutes to calculate wait times and on-time performance.

A bus is considered on time if it arrives at a bus stop no more than 1 minute earlier than scheduled and no more than 5 minutes later than scheduled. This is the same standard used by GRTC.

First, the maximum time between arrivals is found for every bus stop in a bus route or bus route group. Then, the median of the maximum times is found. The result is roughly the current worst-case wait time for that bus route.