What this is
A leaderboard
for Divvy bikes
Roll Call gives every Divvy bike and scooter in Chicago a name, a record, and a ranking, built entirely from the public data the fleet already broadcasts. It's a love letter to the city's hardest-working rides.
How a trip is detected
We watch the feed
There's no GPS trace to ride along with, just a public snapshot of where every vehicle is parked, updated constantly. So we infer the rides from the gaps.
- 01
Check in every minute
We poll Chicago's public Divvy GBFS feed roughly once a minute (the same open data feed any app uses to show you available bikes), and record where each vehicle is sitting.
- 02
Notice the vanishing act
When a vehicle disappears from the feed and later reappears parked somewhere new, that round-trip is a ride. The disappearance is someone unlocking it; the reappearance is where they left it.
- 03
Pin down the endpoints
We log where the ride started and where it ended, the time it took, and a straight-line distance between the two points. Stitch those together over time and a vehicle's whole career takes shape.
- 04
Tally the standings
Miles, trips, neighborhoods touched, and active-day streaks roll up into the all-time and rolling leaderboards. Every vehicle is identified by its plate number. That's its name on the board.
Read the fine print
Honest caveats
Inferring rides from a parking feed means the numbers are a confident sketch, not a survey-grade record. Here's where they get fuzzy.
Distances are estimates
Every distance is the straight line between where a ride started and ended. That's an endpoint estimate, not an odometer reading. A loop that returns to its start can read as zero miles even after a long ride.
Van moves are filtered
Operators truck vehicles around to rebalance the fleet. We flag and drop the moves that look like rebalancing using simple heuristics, but it's a guess, so a few human rides may get cut and a few van moves may slip through.
Identity is the plate
A vehicle is whatever its plate number says it is. If an operator re-plates or retires a unit, its history here reflects the plate, not the physical bike. They usually, but not always, line up.
Coverage starts at launch
We only know what we've watched. Every total is “since launch,” so a long-serving veteran and a brand-new arrival both start their Roll Call record on the same day we began listening.
Privacy
We follow vehicles,
not people
Roll Call is about the bikes: their mileage, their streaks, their wandering. It's never about the people riding them, and the way Divvy works keeps it that way. Every bike is shared, so one bike's history is a chain of different, anonymous riders, not a single person's movements.
Routes run dock to dock, and Chicago's docks are public infrastructure on public streets, not private addresses. It's the same station-level detail Divvy publishes in its own open trip data. We just show it live, built entirely from Divvy's public feed. No accounts, no rider data, nothing that identifies who took a ride.
The data
Public feed, independent project
Data from Divvy's public GBFS feed. Independent project, not affiliated with Divvy or its operators.