Free CDL Study Resources
Every test question in our apps traces back to the CDL Manual. These are the official references — and a few of our own free study tools — that will help you pass.
Official references
FMCSA — Federal Motor Carrier Safety Administration
The federal agency that sets CDL standards. Hours of Service rules, drug & alcohol clearinghouse, and safety regulations.
CDL Manual — your state DMV
Find your state's licensing agency and download the official CDL Manual — the source for every test question.
PHMSA Emergency Response Guidebook (ERG)
The free PHMSA ERG — required for HazMat drivers. Use it together with the in-app ERG reference in our HazMat Test app.
Hours of Service (HOS) regulations
The actual FMCSA rules behind the HOS Quick Check tool inside our CDL Test app.
Study help
Free practice quizzes on this site
Try 240+ free questions across CDL, HazMat and Air Brakes — no signup, no download.
CDL exam blog
Study schedules, exam tips, and breakdowns of the trickiest CDL Manual sections.
Recommended books & tools
Hand-picked study books, pre-trip cheat sheets, and gear that pair well with our apps.