Train for the CDL Written Exam Here
Our CDL Practice Tests get you ready for the road.
Free CDL Practice Tests
Test your knowledge with each of our challenging practice tests. These tests give you the experience of taking your real CDL written exam.
Further below, we will break down all aspects of the CDL test that you need to know.
What Does the CDL Test Look Like?
The above CDL practice tests refer to the CDL written test. This is what you take first. But it’s not the only part of the test.
For the full picture, let’s take a look at the whole the entire CDL test.
The CDL test is broken down as follows.
I. CDL Written Test (for permit)
a. General Knowledge
b. Endorsements
II. CDL Practical/Skills Test
a. Vehicle Inspection Test
b. Road Test
c. Basic Control Skills Test
The written portion of the exam is first. Before you can even step in a truck, you must first take (and pass) this.
In most states, you must be at least 18, and at least 21 to drive interstate, which means between states. You must also hold a valid driver’s license.
The CDL written test contains a General Knowledge exam, an Air Brakes exam, and endorsement exams that will allow you to drive a number of different vehicles. While it’s possible to only take and pass the General Knowledge test, that would greatly restrict what you are able to drive.
Once you pass the written test, you are issued a Commercial Learner’s Permit, which allows you to get behind the wheel to practice driving.
The second part of the CDL exam is the Skills Test, also known as the Practical exam or the Driving Skills Test. This consists of a pre-trip inspection (including an air brakes test), a road test, and basic control skills test (which includes backing up and parking).
Once you pass the CDL Skills Test, you can officially become a truck driver.
The tests are broken down below, but keep in mind that the number of questions and time limits may vary by state.
What Are the Best Resources for the CDL Test?
Before we breakdown the complete CDL written test and the CDL skills test, let’s take a look at the best resources for the CDL test.
Class A Drivers conducted a survey among truck drivers, and that chart is available for you below. Online quizzes and trucking school study guides ranked as the most helpful resources.
Data from Class A Drivers survey
As part of our survey, we also asked what drivers and students found most difficult about the CDL written test. We asked about the General Knowledge and all the endorsements.
As you can see, the General Knowledge and the HAZMAT tests were the most difficult for test takers. We recommend you take our online quizzes for those multiple times to make sure you’re an expert!
CDL WRITTEN TEST
General Knowledge – 50 questions
The General Knowledge CDL test is the easiest portion of the exam and tests your overall knowledge about truck driving and the safe operation of the vehicle.
Questions include how to safely drive down a steep hill, why cargo is required to be covered in many states, night driving, adverse weather conditions, and how a driver would find the gross combination weight, for instance.
If you fail the knowledge tests, you must wait until the next day to retake it and pay the fee once again. The laws vary by state regarding cost and how long you must wait to retake the exam, so make sure to check with your state’s DMV.
Air Brakes – 25 questions
Pretty self-explanatory, the air brakes section tests your knowledge about air brakes!
The Air Brakes test is not technically an endorsement. It simply counts as a restriction if you do not take or do not pass the exam. This is called an L Restriction and prohibits operation of a vehicle with a full air brake system.
HAZMAT (H Endorsement) – 30 questions
Transporting hazardous materials, HAZMAT for short, has its own rules and procedures. This section covers everything related to transporting, loading, unloading, and driving with these substances.
Combination Vehicles – 20 questions
For a Class A CDL, you must pass this portion of the exam since you will obviously be pulling a trailer and not just running around bobtail.
This section covers special considerations that need to be taken when driving a combination vehicle as opposed to a non-combination vehicle.
Doubles /Triples (T Endorsement) – 20 questions
You need the above combination vehicles endorsement to also receive a doubles/triples endorsement. Driving doubles/triples is relatively advanced, and you should only take on these jobs after you have some tractor-trailer experience.
Doubles and triples come with a lot of rules that vary state-by-state regarding the lawful operation of these vehicles, such as length restrictions, etc.
The exam covers weight management, how to couple and uncouple doubles/triples, specific handling characteristics such as stability and braking response, and potential complications such as longer passing times, etc.
Tank Vehicle (N Endorsement) – 20 questions
This endorsement covers the inspection and safe driving rules of driving tank vehicles for hauling liquids. The state CDL manuals cover this briefly, and this test is one of the easier ones.
Passenger (P Endorsement) – 25 questions
If you plan on driving vehicles that can carry 16 or more passengers (including the driver), you need this endorsement. The exam covers how to load/unload passengers, respond to emergencies, effectively handle unruly passengers, etc.
You will need this endorsement before you can move on to a school bus endorsement.
School Bus (S Endorsement) – 25 questions
Similar to the passenger endorsement, this exam focuses on loading and unloading passengers. The difference is that this time, the focus is placed on children.
You are also be tested on the operation of school bus lighting systems, stop signs, crossings, etc. Most states also require a separate physical exam which will be followed by a driving skills test specific to school busses.
Tanker and HAZMAT (X Endorsement)
This endorsement is a combination of two endorsements. If you have a HAZMAT endorsement, your license will be marked with an H. If you have the tanker endorsement, you get an N.
Having both a HAZMAT and tanker endorsement yields the X endorsement, which allows you to drive hazardous materials in a tanker (in addition to on a flatbed or in a trailer).
Having only a HAZMAT will allow you to drive hazardous materials on a flatbed or in a trailer for instance, while the N only allows you to drive tankers that don’t carry hazardous materials such as liquid fuel.
CDL SKILLS TEST
Pre-Trip Inspection (or Vehicle Inspection Test)
The pre-trip inspection (also called the “Vehicle Inspection Test”) is one of the most important and difficult parts of the exam. Each state has their own inspection “checklist” that you must follow, but the fundamentals are the same.
The pre-trip consists of a complete walk-around while looking for specific parts. You need to explain:
- The part name
- What it does
- Why you’re inspecting it
Don’t worry, you don’t need to be an engineer to pass this portion, but you should have a thorough understanding of the vehicle and how it works.
The pre-trip also includes getting inside and inspecting the cab. You will start the engine and test the gauges and controls.
Read our Complete Pre-Trip Inspection Checklist here!
Road Skills
Once you’ve passed the other tests, it’s time to hit the road. The Road Skills test puts you behind the wheel with an examiner in the passenger seat. Fortunately, you should have dozens of hours of practice from your CDL school.
When you make mistakes in this test, each error can fall into one of two categories: automatic failure or acceptable mistake. The former is pretty obvious, you fail automatically and have to retake the road test.
For acceptable mistakes, you may still pass even if you mess up. These errors include shifting a few times, turning too wide, etc. Making too many mistakes will accumulate points, and too many points will result in a failure.
Basic Control Skills
Depending on your state, you may take this section before the road test. The Basic Control Skills test is fairly straightforward and will consist of straight backing, offset backing, parallel parking, and alley docking.
As with most of the CDL exam, the exact test varies by state.
We have a complete section dedicated to the Skills Tests, so read onto the section titled “Get Your CDL”.
TIPS FOR YOUR CDL EXAMS
Get in contact with your state’s DMV and ask for specifics on the exam. When you’re attending a CDL driving school, do the same. Ask the instructor exactly what you will need to know for the exam.
Remember, there are no “minimum hours” you are required to take, so just go at your own pace. If you’re ready in 7 hours, then take the exam and finally get that CDL!
Don’t forget to practice with the tests above.