General Knowledge CDL Practice Test
Practice with real General Knowledge exam questions and detailed explanations. Federally standardized — the same in all 50 states. Rated 4.8 stars by 1,000+ drivers.
Written by CDL holders and exam prep experts · Updated April 2026
Free Questions
10
Passing Score
80%
Time Limit
Typically 60 minutes; varies by testing location
Prerequisites
Required foundation test for all CDL classes (A, B, C)
What is the General Knowledge Test?
The General Knowledge test is required for all CDL applicants. It covers basic commercial driving skills, vehicle inspection, safety procedures, and federal regulations. This is the foundation test that all CDL drivers must pass.
Required foundation test for all CDL applicants
Topic Breakdown
Vehicle Inspection
~12 questions
- Pre-trip inspection procedures
- In-cab inspection items
- Engine compartment checks
Basic Control Skills
~10 questions
- Backing and parking techniques
- Space management
- Speed and distance judgment
Safe Driving
~10 questions
- Following distance and speed management
- Night and weather driving
- Hazard awareness and response
Transporting Cargo
~8 questions
- Weight distribution and securing cargo
- Load limits and weight restrictions
- Cargo documentation
Vehicle Systems
~6 questions
- Engine systems and maintenance
- Electrical and lighting systems
- Suspension and steering systems
Regulations and Safety
~4 questions
- Hours of service regulations
- CDL requirements and restrictions
- Traffic laws and penalties
Free Practice Questions
10 questionsQuestion 1 of 10
The purpose of the retarders is to:
Browse General Knowledge Questions
- 1. The purpose of the retarders is to:
- 2. Retarders:
- 3. The bridge formula:
- 4. Controlled braking:
- 5. Stab braking should not be used on vehicles with:
- 6. The BAC (Blood Alcohol Concentration) for commercial drivers to be considered intoxicated when driving a commercial vehicle is:
- 7. Hydroplaning:
- 8. You are driving a 40-foot vehicle at 55 mph. The road is dry, and visibility is good.What is the least amount of space that you need to have in front of your vehicle?
- 9. How many hours may a CMV driver be on duty within a seven-day period?
- 10. To prevent a load from shifting, there should be at least one tie down for every ____ feet of cargo.
Study Tips
- 1Master the pre-trip inspection sequence thoroughly
- 2Study hours of service regulations and logbook requirements
- 3Practice weight and space management calculations
- 4Learn all vehicle systems and warning signs
- 5Review your state's commercial driver manual completely
CDL Requirements by State
The General Knowledge knowledge test is federally standardized, so the questions are the same nationwide. Age, renewal, and training rules vary by state — find yours below.
| State | Min Age (Intra / Inter) | Renewal | ELDT |
|---|---|---|---|
| California | 18 / 21 | 5 yrs | Required |
| Texas | 18 / 21 | 4 yrs | Required |
| Florida | 18 / 21 | 4 yrs | Required |
| New York | 18 / 21 | 8 yrs | Required |
| Pennsylvania | 18 / 21 | 4 yrs | Required |
| Illinois | 18 / 21 | 4 yrs | Required |
| Ohio | 18 / 21 | 4 yrs | Required |
| Georgia | 18 / 21 | 5 yrs | Required |
| Michigan | 18 / 21 | 4 yrs | Required |
| North Carolina | 18 / 21 | 5 yrs | Required |
| Alabama | 18 / 21 | 4 yrs | Required |
| Alaska | 18 / 21 | 5 yrs | Required |
| Arizona | 18 / 21 | 5 yrs | Required |
| Arkansas | 18 / 21 | 4 yrs | Required |
| Colorado | 18 / 21 | 5 yrs | Required |
| Connecticut | 18 / 21 | 4 yrs | Required |
| Delaware | 18 / 21 | 8 yrs | Required |
| Hawaii | 18 / 21 | 4 yrs | Required |
| Idaho | 18 / 21 | 4 yrs | Required |
| Indiana | 18 / 21 | 4 yrs | Required |
| Iowa | 18 / 21 | 5 yrs | Required |
| Kansas | 18 / 21 | 4 yrs | Required |
| Kentucky | 18 / 21 | 4 yrs | Required |
| Louisiana | 18 / 21 | 4 yrs | Required |
| Maine | 18 / 21 | 6 yrs | Required |
| Maryland | 18 / 21 | 8 yrs | Required |
| Massachusetts | 18 / 21 | 5 yrs | Required |
| Minnesota | 18 / 21 | 4 yrs | Required |
| Mississippi | 18 / 21 | 4 yrs | Required |
| Missouri | 18 / 21 | 6 yrs | Required |
| Montana | 18 / 21 | 4 yrs | Required |
| Nebraska | 18 / 21 | 5 yrs | Required |
| Nevada | 18 / 21 | 4 yrs | Required |
| New Hampshire | 18 / 21 | 5 yrs | Required |
| New Jersey | 18 / 21 | 4 yrs | Required |
| New Mexico | 18 / 21 | 4 yrs | Required |
| North Dakota | 18 / 21 | 5 yrs | Required |
| Oklahoma | 18 / 21 | 4 yrs | Required |
| Oregon | 18 / 21 | 8 yrs | Required |
| Rhode Island | 18 / 21 | 5 yrs | Required |
| South Carolina | 18 / 21 | 5 yrs | Required |
| South Dakota | 18 / 21 | 5 yrs | Required |
| Tennessee | 18 / 21 | 5 yrs | Required |
| Utah | 18 / 21 | 5 yrs | Required |
| Vermont | 18 / 21 | 4 yrs | Required |
| Virginia | 18 / 21 | 8 yrs | Required |
| Washington | 18 / 21 | 5 yrs | Required |
| West Virginia | 18 / 21 | 5 yrs | Required |
| Wisconsin | 18 / 21 | 4 yrs | Required |
| Wyoming | 18 / 21 | 4 yrs | Required |
Career Opportunities
Frequently Asked Questions
The General Knowledge test is required for all CDL applicants. It covers basic commercial driving skills, vehicle inspection, safety procedures, and federal regulations.
General Knowledge Study Resources
What Is a CDL Permit? The Complete CLP Guide
The 7 steps to get a CDL permit (CLP), test requirements, restrictions, and state-by-state costs.
How to Pass the CDL Test
Proven study strategies from drivers who passed on their first try.
CDL Test Questions
How many questions, time limits, and what to expect on test day.
Be Ready for Your General Knowledge Test
1,000+ drivers passed their CDL exam using CDL Answers.
Real questions. Detailed explanations. Know your score before test day.