Data sources and API access
Every dataset this site queries or cites, with access notes and the date each resource ID was verified. If a source moves or a resource ID changes, the accuracy page explains how to report it.
| Source | Access | Used for |
|---|---|---|
| FMCSA QCMobile API | Login.gov account, free WebKey, REST/JSON | Carrier lookup. Live queries only. No bulk ingest. |
| Motus Insur (c5y8-a4uz) | Socrata, no auth required | Insurance filing detail. Resource ID verified 2026-08-19. Pre-Motus files are frozen. |
| eCFR Title 49 | Public web | Every regulatory citation. Linked to the section. |
| FMCSA civil penalties dataset | data.gov download | Background for guide content. Not a live lookup. |
| FMCSA Large Truck and Bus Crash Facts | Background for guide content. Not a live lookup. |