There are more than a dozen CDL written tests, but almost nobody takes all of them. Which tests you sit for is determined by two things: the class of license you are after (Class A or Class B) and the specific cargo or vehicle your job involves. This page lists every practice test on the site, but the more useful question is which ones apply to you — so start there.
Which tests will you actually take?
If you want a Class A CDL
Class A is the license for tractor-trailers — the over-the-road, dry van, reefer, and flatbed work most people picture when they say "truck driver." You will take three written tests: General Knowledge, Combination Vehicles, and Air Brakes. Air Brakes is technically optional, but skipping it puts a restriction on your license that bars you from driving any air-braked vehicle — which is nearly every commercial truck. From there, add endorsements based on what you will haul.
If you want a Class B CDL
Class B covers straight trucks, dump trucks, garbage trucks, large buses, and transit vehicles. You will take General Knowledge (Class B) and, in nearly all cases, Air Brakes, since most Class B vehicles are air-braked. School bus drivers add both the Passenger and School Bus endorsements on top of that.
If you will haul hazardous materials or pull tankers
The HAZMAT endorsement requires both a written test and a TSA background check that can take 30 to 60 days — apply for the background check before your DMV appointment so the wait runs in parallel with your studying. Fuel haulers typically need HAZMAT plus Tanker, a combination sometimes informally called the X endorsement.
Not sure where you land? The Which CDL tool walks you through two questions and maps out your class, your tests, and the endorsements for the job you want.
Every CDL written test at a glance
Question counts and the audience for each test, so you can see at a glance what is on your list. Most states require 80% to pass each written test; practice until you are consistently above 90%.
| Test | Questions | Who needs it |
|---|---|---|
| General Knowledge (Class A) | 50 | Every Class A applicant |
| General Knowledge (Class B) | 50 | Every Class B applicant |
| Air Brakes | 25 | Any vehicle with air brakes (almost all trucks) |
| Combination Vehicles | 25 | Every Class A applicant |
| HAZMAT | 30 | Hauling hazardous materials (plus a TSA check) |
| Tanker | 20 | Liquid or gas tank vehicles |
| Doubles / Triples | 20 | Pulling two or three trailers |
| Passenger | 20 | Vehicles carrying 16+ passengers |
| School Bus | 20 | School bus drivers (plus Passenger) |
| Pre-Trip Inspection | Verbal | Every applicant (spoken exam, not multiple choice) |
The mistake we see most on the written side is people trying to knock out every test in one sitting to "get it over with."
General Knowledge is the backbone — the rules it covers show up again, in different form, on almost every other test. Students who pass it solidly find the endorsement tests much easier, because they are reading the same federal logic from a new angle instead of starting cold. We tell every class to get General Knowledge to a confident 90% before moving on, then take Air Brakes and Combination, then the job-specific endorsements last.
The other thing: do not take endorsement tests you do not need just because they are there. Each one is a separate fee at the DMV and a separate thing to keep current. Take what your job requires, pass it well, and stop.
How to use these practice tests
Every test here draws from the same FMCSA source material your state's official CDL manual uses, and each one reshuffles its questions on every attempt, so you cannot accidentally memorize an order. After each question you will see whether you were right, a short explanation, and the topic it came from — so every attempt doubles as a study session.
The reliable path: read your state's CDL manual once, take the matching practice test to find your weak spots, re-read just those sections, then retake until you are hitting 90%+ on three runs in a row. For more on the exam format and what to bring to the DMV, see CDL test info and the full step-by-step guide to getting your CDL.