Getting a commercial driver's licence means passing a set of written knowledge tests before you ever touch a truck for the skills exam. Which ones you take depends on the class of licence you want and what you plan to haul. Everybody sits general knowledge. After that it depends.
The knowledge test every commercial driver takes, whatever class or endorsement they are after.
Required before you may drive any commercial vehicle with air brakes.
Required for a Class A licence. Coupling and uncoupling, off-tracking, trailer brakes and the handling of a vehicle that is jointed in the middle.
The H endorsement. Placarding, shipping papers, loading and segregation rules, and what to do when something leaks.
The N endorsement. Surge, baffles, bulkheads, high centre of gravity and the way a part-full tank changes how a vehicle stops and turns.
The T endorsement. Coupling and uncoupling multiple trailers, converter dollies, crack-the-whip and the inspection points a second trailer adds.
The P endorsement. Pre-trip and post-trip checks on a bus, loading and unloading, standee lines, and handling passengers on the road.
The S endorsement, taken alongside the passenger endorsement. Danger zones, mirror adjustment, loading and unloading students, and railroad crossings.
A study drill for the pre-trip inspection.
Short sets drawn from the same bank, for when you already know which part caught you out. They are practice, not a test anyone sets.
The general knowledge test is the one nobody can skip. It covers inspecting a vehicle, controlling it, managing the space around it, controlling your speed, spotting hazards early, handling emergencies and dealing with cargo. The subject list is federal, set out in 49 CFR 383.111, which is why the material barely changes when you cross a state line.
Most states ask fifty questions and want forty right. A handful differ, and where they do we cite the state's own handbook rather than guessing.
If the vehicle you will drive has air brakes, you take the air brakes test. Failing it does not stop you getting a licence; it puts an air brake restriction on it, which rules out most driving work. If you want a Class A licence you take combination vehicles as well, because a jointed vehicle behaves nothing like a straight truck.
After that come the endorsements. Hazardous materials, tanker, doubles and triples, passenger and school bus each have their own test, and each has its own habits of catching people out. Tanker questions are mostly about surge and centre of gravity. Hazmat is mostly placarding and paperwork. School bus is mostly danger zones and railroad crossings.
A failed knowledge test costs a fee and usually a day off work, and some states make you wait before you can try again. The people who fail are rarely the ones who did not study. They are the ones who read the handbook once, felt like they knew it, and never tested themselves on the numbers.
That is what these tests are for. Every question is written from an official handbook or from the federal regulations, and every one names the document, edition and page it came from, along with the month a person last checked it against that document. If you think we have something wrong, you have everything you need to go and prove it.
At the end of every run you get a breakdown by subject rather than a single score, because a driver sitting at ninety per cent overall but forty per cent on air brake material does not need to revise everything again. They need to revise one thing. You can then retry only the questions you got wrong, which is the fastest way to close a gap before you book.
Pick a test below and start. Nothing here is locked, and you never need an account.
Every question on every one of these is free, and each answer names the handbook page it came from.
Every question names the handbook, section and page it was read from, so you can check the answer instead of taking our word for it.
How we write these