How Many Questions Are on the CDL Permit Test?

Starting a career in trucking begins with one crucial step: passing the CDL permit test. Without this permit, you cannot move forward to behind-the-wheel training or eventually obtain your full Commercial Driver’s License (CDL). For many aspiring drivers, the first big question is: how many questions are on the CDL permit test? The answer is not the same for everyone, as it depends on whether you are pursuing a Class A or Class B CDL and whether you plan to add endorsements such as HazMat, Tanker, or Passenger.

How Many Questions Are on the CDL Permit Test? (Quick Breakdown)

One of the first things every aspiring commercial driver wants to know is: how many questions are on the CDL permit test? The answer depends primarily on which CDL class you are pursuing and whether you plan to add endorsements. While exact numbers can vary slightly by state, the structure of the test is standardized across the U.S. under FMCSA regulations.

At its core, the CDL permit test is divided into several key sections. Every applicant must take the General Knowledge test, and depending on the class of license (A or B), additional tests such as Air Brakes or Combination Vehicles will also be included. Each test section has a set number of multiple-choice questions, and every candidate must score at least 80% to pass.

CDL Class A Permit Test: 95 Questions

The Class A CDL permit test is designed for drivers who plan to operate combination vehicles such as tractor-trailers, tanker trucks, and flatbeds. Because these vehicles involve more complex operations—especially towing heavy trailers—the test is more extensive than for Class B.

The Class A test consists of:

• General Knowledge Test – 50 questions
  Covers topics like vehicle inspections, road safety, cargo securement, and rules of the road.
• Air Brakes Test – 25 questions
  Required if the vehicle you intend to drive uses an air brake system. Covers inspection, safe use, and emergency handling.
• Combination Vehicles Test – 20 questions
  Required because Class A vehicles involve trailers. Covers coupling/uncoupling, handling trailers, and safety checks.

Total number of questions: 95
To pass, you must answer at least 76 questions correctly across all sections combined (80% passing rate).

CDL Class B Permit Test: 75 Questions

The Class B CDL permit test is intended for drivers who plan to operate single commercial vehicles such as box trucks, straight trucks, buses, or dump trucks. These vehicles are smaller and less complex than Class A combination vehicles, so the test is slightly shorter.

The Class B test consists of:

• General Knowledge Test – 50 questions
  Covers the same core safety and legal requirements as the Class A exam.
• Air Brakes Test – 25 questions
  Required if the Class B vehicle uses an air brake system.

Total number of questions: 75
To pass, you must answer at least 60 questions correctly (80% passing rate).

Unlike Class A, the Class B test does not include a combination vehicles section, since Class B vehicles do not typically tow large trailers. However, drivers may still choose to take additional endorsement exams to expand their driving privileges.

The 80% Passing Rule Explained

No matter which class of CDL you are pursuing, the passing standard remains the same: a minimum score of 80%. This means:

• On the General Knowledge test (50 questions), you must get at least 40 correct.
• On the Air Brakes test (25 questions), you must get at least 20 correct.
• On the Combination Vehicles test (20 questions), you must get at least 16 correct.

If you fail to meet the 80% threshold in any one section, you will not receive your Commercial Learner’s Permit (CLP). This rule ensures consistency and safety across all states, guaranteeing that every new driver has the baseline knowledge needed before moving on to behind-the-wheel training.

State Variations vs. Federal Standards

Although the FMCSA (Federal Motor Carrier Safety Administration) sets the baseline rules and passing criteria, each state administers its own CDL permit tests through the Department of Motor Vehicles (DMV) or equivalent agency. Because of this, there can be slight variations in:

• Exact number of questions – Some states may add or reduce a few questions depending on their testing format.
• Time limits – Most states give you 60 minutes for General Knowledge, but this can vary.
• Endorsement availability – While HazMat, Passenger, and Tanker endorsements are universal, some states allow you to test for them immediately with your CLP, while others require waiting until after you hold the permit.

Despite these small differences, the overall federal standards remain consistent nationwide:

• Every state must include General Knowledge in the CDL permit test.
• Endorsements and specialized sections must meet FMCSA content requirements.
• The 80% passing threshold cannot be lowered.

In practical terms, this means that whether you test in California, Texas, Florida, or New York, you are facing a test that is structured very similarly and held to the same federal expectations.

CDL Permit Test Sections Explained

The CDL permit test is not a single uniform exam—it is a series of knowledge tests, each designed to measure whether you are ready to safely operate commercial motor vehicles (CMVs). Every applicant, regardless of the CDL class they pursue, must take the General Knowledge Test, while other sections depend on the class of license and the type of vehicle you plan to drive. Below is a detailed breakdown of the most important sections.

General Knowledge Test

The General Knowledge Test is the foundation of the CDL permit exam and is required for all applicants, whether pursuing a Class A, B, or C CDL. It evaluates whether you understand the critical rules of the road and basic safety practices for operating commercial vehicles.

Covered topics include:

• Vehicle inspections – Identifying mechanical problems before they become safety hazards, pre-trip inspection requirements, and preventive maintenance routines.
• Road safety practices – Defensive driving strategies, avoiding collisions, safe lane changes, managing blind spots, and handling poor weather conditions.
• Cargo handling – Understanding how to secure freight, weight distribution requirements, and how cargo shifts can affect balance and control.
• Alcohol and drug awareness – Federal BAC limits for CDL holders, the consequences of impairment, and penalties for substance-related violations.

Structure of the test:

• 50 questions
• Passing score: At least 40 correct (80%)
• Time limit: Usually 1 hour, but states may adjust slightly

Because this section covers the broadest and most critical topics, it is often viewed as the most important part of the CDL permit test. Without passing it, you cannot earn your Commercial Learner’s Permit (CLP) and cannot move forward with behind-the-wheel training.

Air Brakes Test

Commercial vehicles are often equipped with air brake systems, which differ from standard hydraulic brakes in both operation and complexity. To legally operate a vehicle with air brakes, you must pass the Air Brakes Test.

Covered topics include:

• System components – Compressors, tanks, valves, brake chambers, and other key parts.
• Inspection procedures – Identifying air leaks, measuring pressure levels, and ensuring the system is functioning correctly.
• Safe braking techniques – How to apply brakes properly, avoid brake fade, and monitor warning indicators.
• Emergency procedures – Correct responses when faced with system malfunctions or low pressure situations.

Structure of the test:

• 25 questions
• Passing score: At least 20 correct (80%)

If you fail this section, you can still earn a CDL, but your license will carry an “L” restriction, which prohibits you from operating vehicles equipped with air brakes. Since most commercial trucks use air brakes, passing this section is considered essential for nearly all Class A applicants.

Combination Vehicles Test

The Combination Vehicles Test is required for anyone applying for a Class A CDL, which covers vehicles that tow trailers. Driving these vehicles presents unique challenges compared to single-unit trucks, and this section ensures that applicants understand those differences.

Covered topics include:

• Coupling and uncoupling – Proper steps for safely attaching and detaching trailers.
• Inspection requirements – Ensuring all connections are secure, brakes are working, and trailers are aligned properly.
• Driving practices – Adjusting speed, braking, and cornering when pulling trailers.
• Trailer dynamics – Managing sway, off-tracking, and rollover risks caused by trailer movement.

Structure of the test:

• 20 questions
• Passing score: At least 16 correct (80%)

This section is critical because towing trailers requires heightened awareness, precision, and control. Without it, you cannot qualify for a Class A CDL.

CDL Endorsements: Extra Questions You May Need

In addition to the core tests, many drivers choose to pursue endorsements—special qualifications that allow you to carry specific types of cargo or operate certain types of vehicles. Each endorsement requires passing an additional written knowledge test, which adds more questions to your overall permit exam.

Hazardous Materials (HazMat) Endorsement

The HazMat endorsement (H) is one of the most regulated in the trucking industry, as it involves transporting dangerous goods that could threaten public safety if mishandled.

Covered topics include:

• Hazard classes: Explosives, flammable liquids, gases, corrosives, and radioactive materials.
• Placards and labeling: Correctly identifying and marking hazardous shipments.
• Emergency procedures: Steps to take in the event of spills, leaks, or accidents.
• Security measures: Federal rules for safeguarding hazardous loads, including background checks and restricted access.

Structure of the test:

• 30 questions
• Passing score: At least 24 correct (80%)

To earn this endorsement, drivers must also complete a TSA background check and fingerprinting, making it one of the most demanding certifications to obtain.

Tanker Vehicles Endorsement

The Tanker Vehicles endorsement (N) is required for drivers who haul large liquid loads in tank trucks. Because liquids behave differently than solid cargo, this test focuses on the unique physics of driving with liquid freight.

Covered topics include:

• Liquid surge dynamics: How shifting liquid affects braking and stability.
• Baffle systems: How compartments inside tanks reduce surge.
• Driving techniques: Adapting cornering, braking, and acceleration to prevent rollovers.
• Inspection: Checking tanks for leaks and ensuring valves and seals are secure.

Structure of the test:

• 20 questions
• Passing score: At least 16 correct (80%)

Often, tanker and hazardous materials tests are combined into an X endorsement, which authorizes drivers to haul hazardous liquids such as fuel.

Doubles and Triples Endorsement

The Doubles/Triples endorsement (T) allows drivers to tow two or three trailers simultaneously. These vehicles are harder to control, requiring advanced knowledge of safety procedures.

Covered topics include:

• Coupling and uncoupling multiple trailers safely and securely.
• Vehicle handling: Adjusting for the extra length, weight, and stopping distance.
• Increased risks: Rollover potential, jackknifing, and trailer separation.
• Inspection protocols: Checking connections and brake systems for multiple trailers.

Structure of the test:

• 20 questions
• Passing score: At least 16 correct (80%)

Because of the higher risk involved, many companies only assign doubles and triples to experienced drivers.

Passenger Transport Endorsement

The Passenger endorsement (P) is mandatory for drivers who operate buses or other vehicles that carry passengers. This test ensures that applicants understand not only vehicle safety but also passenger protection.

Covered topics include:

• Loading and unloading procedures – Safely assisting passengers, including those with disabilities.
• Mirror usage and blind spot checks – Ensuring visibility when maneuvering.
• Emergency response – Evacuation procedures and passenger safety in emergencies.
• General safety standards – Preventing accidents and maintaining a safe environment inside the bus.

Structure of the test:

• 20 questions
• Passing score: At least 16 correct (80%)

This endorsement is required for charter buses, public transit vehicles, and some school buses (school bus drivers also need a separate S endorsement).

Start Your CDL Journey with ELDT Nation

If you are ready to take the next step toward a rewarding trucking career, ELDT Nation provides everything you need to succeed. Our training is not only comprehensive but also FMCSA-approved, meaning your results are valid in all 50 states and automatically reported to the federal registry. You won’t need to worry about extra paperwork—we handle the process for you.

Unlike traditional classroom courses that lock you into rigid schedules, our program is 100% online. You can study at your own pace, from anywhere, and on any device. Whether you prefer late-night sessions or early-morning reviews, the flexibility of online learning ensures that your education fits seamlessly into your life.

Every course includes interactive video lessons, quizzes, and practice tests that mirror the real CDL permit exam. You will not only memorize the answers but also truly understand the principles of safe driving, making you more confident when it’s time to sit for the test. With full access until you pass, there is no pressure—you can revisit lessons and quizzes as many times as necessary until you feel fully prepared.

ELDT Nation also supports drivers aiming for special endorsements such as HazMat, Tanker, Passenger, and Doubles/Triples. This means you can expand your opportunities, qualify for higher-paying jobs, and position yourself for long-term success in the trucking industry.

When you enroll, here’s what comes next:

• Step 1: Access our FMCSA-approved courses and begin your online learning journey immediately.
• Step 2: Pass your theory training with confidence, knowing your results are automatically reported to FMCSA and DMV.
• Step 3: Connect with a behind-the-wheel training provider to complete your hands-on practice.
• Step 4: Earn your CDL, launch your trucking career, and start exploring opportunities to make a high, stable income.

With trucking salaries averaging over $90,000 per year and a nationwide shortage of qualified drivers, there has never been a better time to start your journey.

Browse our courses today, get your free CDL preparation guide, and take the first step toward becoming a professional truck driver with ELDT Nation.