CDL practice tests, one federal bank
Commercial licensing is federal, so these three papers are the same questions whichever state you license in. 49 CFR Part 383 sets what you have to know and fixes the pass mark at 80 percent.
CDL general knowledge
FL30 questions, 24 right clears the federal 80 percent bar. Everyone takes this one, whatever class you are after.
CDL air brakes
FL25 questions, 20 right clears the federal 80 percent bar. Skip it and an air brake restriction goes on the license.
CDL combination vehicles
FL25 questions, 20 right clears the federal 80 percent bar. Required for Class A, which is most tractor-trailer work.
The pass mark is 49 CFR 383.135(a)(1). Paper lengths are ours: the regulation fixes the mark, not how many questions go on the paper.
Why one bank covers every state
A state issues the license, charges for it and books the appointment. It does not write the syllabus: 49 CFR Part 383 sets the knowledge a commercial applicant has to demonstrate, 383.135(a)(1) fixes the pass mark, and the book agencies hand out is the AAMVA model Commercial Driver’s License Manual rather than one of their own drafting. Car permit rules run the other way, which is why every car paper here carries a layer written from that state’s own statutes and these three do not.
| State | Car pass mark, set by the state | CDL pass mark, set federally |
|---|---|---|
| FloridaFLHSMV | 80%FLHSMV, Class E Knowledge Exam and Driving Skills Test, checked September 9, 2026 | 80%49 CFR 383.135(a)(1) |
| TexasTxDPS | 70%Texas Driver Handbook DL-7 (rev. January 2026), Chapter 1; 37 TAC s. 15.52, checked September 9, 2026 | 80%49 CFR 383.135(a)(1) |
| CaliforniaCalifornia DMV | 80%California DMV instruction permits page, checked September 9, 2026 | 80%49 CFR 383.135(a)(1) |
The car figures come from the state and do not have to agree with each other. The commercial column cannot vary.
What each paper decides
- General knowledge. The first paper for every applicant, whatever the eventual class or endorsement looks like.
- Air brakes. Fail or skip it and an air brake restriction goes on the license, forbidding any vehicle whose braking system runs on air. Nothing here is rounded for readability either: the low air pressure warning has to activate before pressure falls below 60 psi, under 49 CFR 393.51.
- Combination vehicles. Required for Class A. Rearward amplification, off-tracking, and the coupling sequence down to the glad hands and the tractor protection valve.
Which parts of 49 CFR these questions cite
Under every answer sits the regulation, or the piece of FMCSA guidance, the question was built from, so the federal claim on this page can be checked rather than taken on trust. Four parts of Title 49 do most of the work.
- Part 383, commercial driver standards. The 80 percent pass mark at 383.135(a)(1), the definition of a commercial motor vehicle at 383.5, the 0.04 alcohol threshold at 383.51 and the duty to report a conviction to your employer at 383.31.
- Part 392, driving a commercial vehicle. Cargo checks at 392.9, railroad crossings at 392.10, warning devices after stopping at 392.22 and the alcohol rules at 392.5.
- Part 393, parts and accessories. The low pressure warning at 393.51, brake adjustment at 393.47 and air tank draining at 393.50.
- Part 396, inspection and maintenance. The post-trip report at 396.11, and the out-of-service conditions that mean a vehicle does not move at all.
Title 49 carries no copyright and the model manual very much does, so every question here was drafted from the regulation text. No paragraph of that manual has been reworded into one.
Common questions
Is the CDL knowledge test the same in every state?
The knowledge is. 49 CFR Part 383 sets what a commercial applicant has to demonstrate and fixes the pass mark at 80 percent, and the book behind the exam is the AAMVA model Commercial Driver’s License Manual, which most agencies reprint with only their own front matter changed. Your state decides the price, the paperwork and how long you wait for an appointment. It does not decide the syllabus.
What score do you need to pass a CDL knowledge test?
Eighty percent, set by federal regulation at 49 CFR 383.135(a)(1), which requires an applicant to answer at least 80 percent of the questions correctly. A state runs its own fees and scheduling, but it may not pass someone below that mark.
What happens if you fail the air brakes test?
An air brake restriction goes onto the license, forbidding you from operating any vehicle whose brakes run on air. Nearly every tractor unit qualifies, so the restriction closes the work off rather than narrowing it, which is why almost every applicant takes air brakes right after general knowledge.
Which vehicles need a CDL?
Under the federal definition at 49 CFR 383.5, a commercial motor vehicle is one with a gross combination or vehicle weight rating of 26,001 lb or more, or designed to carry 16 or more people including the driver, or carrying hazardous materials in quantities requiring placards.
Car and motorcycle tests: all US practice tests by state. How this material is written and checked: who writes this.
Sources: 49 CFR Parts 383, 392, 393 and 396; Federal Motor Carrier Safety Administration guidance; Florida Department of Highway Safety and Motor Vehicles; Texas Department of Public Safety, Driver License Division; California Department of Motor Vehicles. Original practice questions, not the official examination questions, and not affiliated with or endorsed by the FMCSA or any state licensing agency.