How Uber Knows Your Driver Is 7 Minutes Away Uber's DeepETA system predicts arrival times by dividing roads into roughly 100 million segments and using driver GPS pings collected every four seconds as live traffic telemetry, then forecasting segment crossing times up to three hours ahead. The deep learning model answers about 2 million forecast requests per second, and a second correction model trained on millions of completed trips fixes systematic errors in the routing engine's segment sums. Uber says DeepETA improved long-trip arrival accuracy by 6%, worth an estimated $100 million a year in gross bookings. Hello, I'm Maneshwar, and I'm building LiveReview — a blast-radius aware AI code review built for your business-critical systems. Star us https://github.com/HexmosTech/LiveReview/ to help devs discover the project, give it a try, and share your feedback to help improve the product. Your Uber says the driver is 7 minutes away. They show up in 7 minutes. That is not a lucky guess, that is one of the more quietly insane systems in consumer tech, and it is worth taking apart. Uber does not think about roads, it thinks about road segments . A single road gets cut into a handful of pieces, and globally Uber is tracking around 100 million of these segments. Each segment has a number attached to it: how long it takes to cross, right now. To get from your driver to you, the routing engine finds the fastest path through these segments and adds up the crossing times along the way. That sum is your ETA. Simple enough, except that number, "how long it takes to cross this segment", is not a constant. It is 20 seconds at 2am and 2 minutes at 6pm on a Friday, on the exact same 200 meters of road. The obvious move is to buy this traffic data from someone who already maps the whole planet. Uber doesn't. Uber measures it. Every driver on the platform is already pinging their location every 4 seconds, because that's what the app needs to do anyway. That stream is basically free traffic telemetry. Every time a driver crosses a segment, Uber now knows, to the second, how long that segment just took. Multiply that by every active driver and you get a live traffic sensor network that nobody had to install a single camera for. Here's the catch. Live measurements only tell you what a segment did in the past few minutes. Your ETA needs to know what it's going to do while your driver is still en route to you, which could be 15 minutes from now. So in 2022, Uber shipped a deep learning system called DeepETA , and it does not just average recent history. It refreshes these forecasts for every segment, for the next 3 hours, every few minutes, and answers roughly 2 million forecast requests a second, making it one of the busiest models running inside Uber. Uber Engineering: DeepETA https://www.uber.com/us/en/blog/deepeta-how-uber-predicts-arrival-times/ php flowchart LR A Driver GPS pings