About What Breaks Next

What Breaks Next reads NHTSA's public complaint database and turns it into a per-vehicle answer to "what's most likely to break next, and around what mileage." Every complaint is classified by a language model run offline, then aggregated into a ranking - no live inference, no accounts, no tracking.

See the methodology page for exactly how accurate that classification is, what biases the underlying data carries, and what this site's numbers can and can't support.

I'm Quinn Kozak, a computer science student at the Milwaukee School of Engineering. I built What Breaks Next on my own, and this page is the only thing on the site that is anyone's opinion.

I am not a mechanic. I have never diagnosed a car in my life. That turns out not to matter much here, because this site does not diagnose anything either. It reads what owners reported to the federal government and counts it carefully, which is a different job.

The data has been public for decades. NHTSA collects complaints from vehicle owners and publishes all of them. The trouble is that the usual way of reading it reports raw complaint totals, and a raw total tells you more about how many of a car were sold and whether it had a big recall than about what is likely to go wrong with yours. Nobody was answering the question people actually ask, which is what tends to fail around the mileage I am sitting at right now.

So I built that. Roughly 600,000 complaints across 757 vehicles were read and categorized by a language model running on my desktop, then aggregated into rankings you can filter by your own odometer. The methodology page explains how accurate that classification is, where it is weakest, and which numbers you should not lean on. I would rather you read that page than take this one on faith.

The 757 vehicles are a starting point, not the whole road. I plan to add more based on what people actually search for.

This site is not affiliated with NHTSA, is not endorsed by them, and is not a reliability rating. It is a summary of what owners said.