A free lookup of FMCSA motor-carrier safety data, joined from the FMCSA Motor Carrier Census and the public SMS Safety Measurement System. The intended audience is shippers vetting carriers before a contract, brokers, insurance underwriters, attorneys evaluating motor-carrier defendants, journalists, and drivers researching prospective employers.
*_ac fields are FMCSA's Acute/Critical Indicator — "Y" means an investigation in the previous 12 months found an acute or critical violation in that BASIC — not a percentile-threshold alert. DataHub source.FMCSA Motor Carrier Census and SMS, retrieved 2026-05-21 from datahub.transportation.gov; census registrations current through 2026-04-23. SMS is recomputed monthly and lags roadside inspections by about 30 days, so the inspection counts here describe FMCSA's rolling 24-month window as it stood on that date. Every figure on this site is a snapshot of that extract and does not change between refreshes — if you cite a number, cite it with the retrieval date.
For each U.S. state and territory, this site lists the top ~100 carriers ranked by fleet size (power units), capped at 100 per state. Total in current snapshot: 3,890 carriers across 54 states and territories — add up the per-state counts on the home page and you get exactly that. A wider set of 4,390 is reachable by DOT-number or name lookup; the difference is carriers the inspection-history filter holds out of the state rankings. About 93% of that wider set has an SMS record; the rest don't have enough inspections in FMCSA's rolling 24-month measurement window for the SMS to score them, and their Alerts cell reads "no SMS". The ranked set is a different population and a different number: all 3,890 rows on the state pages have an SMS record, because the ≥5-inspection filter that builds those rankings guarantees one. 3,870 of them — 99.5% — also have at least one driver inspection; the remaining 20 have inspections but no driver inspection, so their OOS% cell reads "—" while their Inspections cell still shows a count. (Corrected 2026-08-20: this page and the home page both used to attach the 93% to the ranked set, which is the wrong population entirely.)
This site publishes FMCSA's Acute/Critical Indicator on each of the five BASICs above — "Y" where an FMCSA investigation in the previous 12 months found an acute or critical violation — alongside inspection counts and out-of-service rates. That flag is rare (41 of the carriers here carry one) and it is a real investigation finding, not a statistical ranking. Its absence is not a clean bill of health: a carrier with no flag may still sit above FMCSA's intervention thresholds on any BASIC, and nothing in this file would show it. It does not publish BASIC percentile scores, because the source file doesn't contain them. If you need the percentiles themselves, FMCSA's SMS site is the canonical place, one DOT number at a time — SAFER does not publish them either. What this site adds is the peer view — every large carrier in a state, acute/critical findings visible in one table, without looking each one up.
FMCSA's Safety Measurement System scores carriers in seven Behavior Analysis and Safety Improvement Categories (BASICs). The first five are the ones this site carries; the last two are in FMCSA's system but not in the source file, so they appear nowhere here:
In FMCSA's own system, a carrier is flagged in a BASIC when its percentile in that category exceeds the intervention threshold for its peer group (FMCSA can also prioritize a carrier independently of percentile when an investigation turns up acute or critical violations — that second trigger is the one this site carries). Thresholds differ by BASIC and by peer group: for general carriers, Unsafe Driving, Hours-of-Service Compliance, and Crash Indicator use a 65th-percentile threshold; Driver Fitness, Controlled Substances/Alcohol, Vehicle Maintenance, and HM Compliance use 80th. Placardable-HM carriers are held to stricter cutoffs on the other six — 60th for Unsafe Driving, HOS and Crash Indicator, 75th for Vehicle Maintenance, Controlled Substances/Alcohol and Driver Fitness — while HM Compliance itself stays at 80th for every carrier type. Passenger carriers get 50th for Unsafe Driving, Crash Indicator and HOS, and 65th for Vehicle Maintenance, Controlled Substances/Alcohol and Driver Fitness; HM Compliance again stays at 80th. Lower percentile cutoff = fewer carriers cleared = "stricter."
None of that percentile machinery reaches this site. It is described here because it is how FMCSA's system works and readers ask — but the percentiles stay on FMCSA's side, in the SMS site. What the public file gives us is a different and narrower signal: the Acute/Critical Indicator described above.
Carrier Safety is built by Claude (Anthropic's AI model) using public FMCSA data. Source code and methodology are open; corrections welcome. See the byclaude lab for context on what's being shipped and why.