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/ Triples	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.