CDL Test Overview
The CDL Test consists of a general test, one or more endorsement tests, and an air brakes test. The tests that you will take depend on the license classification that you are obtaining (Class A, B, or C) and the type of vehicle that you will be driving (e.g., Tanker, Double/Triple, Passenger Bus).
CDL General Test Overview
Drivers of every CDL class need to pass a General Knowledge exam which covers topics such as:
- Driving Safely
- Vehicle Inspection
- Basic Control of Your Vehicle
- Shifting Gears
- Seeing
- Communicating
- Controlling Speed
- Managing Space
- Seeing Hazards
- Distracted Driving
- Aggressive Drivers/Road Rage
- Driving at Night
- Driving in Fog
- Driving in Winter
- Driving in Very Hot Weather
- Railroad-highway Crossings
- Mountain Driving
- Driving Emergencies
- Antilock Braking Systems (ABS)
- Skid Control and Recovery
- Crash Procedures
- Fires
- Alcohol, Other Drugs, and Driving
- Staying Alert and Fit to Drive
- Hazardous Materials Rules For All Commercial Drivers
- Cargo Transport
To study for the General Test, we recommend you start here.
CDL Endorsement Test Overview
You must pass endorsement tests depending on the type of CMV that you will be driving. The endorsement tests are described below.
Tank endorsement – to drive a commercial tank vehicle (over 26,000 pounds) designed to transport any liquid or gaseous material within a tank that is permanently or temporarily attached to the vehicle or chassis. Does not include portable tanks having a rated capacity under 1,000 gallons.
Double and triple trailer endorsement – to pull double and triple trailers.
Passenger endorsement – to drive any vehicle, except a school bus, designed to carry 16 or more persons, including the driver.
School bus endorsement – to drive a vehicle designed to carry 16 or more persons, including the driver that is marked with or displays the words “school bus” and is used to transport students to or from school and may be used to transport students to or from authorized school activities. A school bus manufacturer, dealer or mechanic is not required to have the endorsement while operating a school bus that is not transporting students. A driver must qualify for a passenger endorsement before obtaining a school bus endorsement.
Hazardous materials endorsement – to drive any vehicle carrying hazardous materials that require placards or transporting any amount of material listed in the Federal Department of Health and Human Services regulations as a select agent or toxin.
You can study for the endorsements by using our CDL Practice Tests.
CDL Air Brakes Test
If you plan on driving any CMV equipped with air brakes, you must take and pass the air brakes test to remove the air brakes restriction from your CDL. The air brakes test is different than the endorsement tests because the air brakes test works as a restriction instead of an endorsement. If you do not pass the air brakes test, your CDL will bear a mark of restriction which means that you are not authorized to drive a CMV with air brakes.
You can study for the Air Brakes Test with our CDL Practice Tests.
Which CDL Tests Should I Study For
The following table summarizes which exams you should study based on the license you plan on obtaining.
License Class |
General Knowledge |
Passenger Transport |
Combination Vehicles |
Hazardous Materials |
Tanker |
Double/ |
Air Brakes |
Class A |
X |
|
X |
If needed |
If needed |
If needed |
X |
Class B |
X |
If needed |
|
If needed |
If needed |
|
If needed |
Class C |
X |
If needed |
|
If needed |
If needed |
|
|
Our CDL Practice Tests will help with both the general knowledge tests and the endorsements.
CDL Test Summary
The following table summarizes the various exams.
Knowledge Test |
Number of Questions |
Questions required to get right to pass at 80% |
General Knowledge Test |
50 |
40 |
Passenger Transport Test |
20 |
16 |
Combination Vehicles Test |
20 |
16 |
Hazardous Materials Test |
30 |
24 |
Tanker Test |
20 |
16 |
Doubles/Triples Test |
20 |
16 |
Air Brakes Test |
25 |
20 |
Every state license agency can provide more details on the requirements for a CDL license as well as a detailed CDL manual.