CDL Practice Test California
Going commercial? This CDL practice test California page has four quizzes that mirror the general knowledge, air brakes and combination topics on the commercial learner’s permit tests, with a mock exam to finish.
CDL Practice Test California: 4 Free Quizzes
Explanations follow every answer. Treat any score under 80 percent as a topic to review before your DMV visit.
What the California CDL permit tests cover
You earn a commercial learner’s permit (CLP) by passing a vision exam and the knowledge tests for your class and endorsements. In California, commercial licensing is handled by California Department of Motor Vehicles (DMV), and the tests are written from the official commercial driver manual.
Quiz 1: California CDL classes and permit rules
Classes, endorsements, disqualifications and alcohol limits, with a couple of California-specific questions.
Quiz 2: Driving safely
Seeing far ahead, following distance, curves, grades, skids and backing.
Quiz 3: Air brakes and vehicle inspection
Air brake pressures, leak tests, tire tread and pre-trip checks.
Full mock exam
50 mixed questions with combination vehicles, cargo, hours of service and emergencies.
CDL classes at a glance
Which class you need depends on the weight of the vehicle and what it carries.
| Class | Covers | Typical vehicles |
|---|---|---|
| Class A | Combination vehicles with a GCWR of 26,001 lbs or more, towing a unit over 10,000 lbs | Tractor-trailers, tanker combinations |
| Class B | A single vehicle with a GVWR of 26,001 lbs or more, towing 10,000 lbs or less | Straight trucks, large buses, dump trucks |
| Class C | Vehicles not in A or B that carry 16 or more people or placarded hazardous materials | Small buses, hazmat vans |
The California DMV CDL page explains classes, endorsements and testing in full.
From CLP to CDL: the road ahead
Before you test
- Complete required entry-level driver training (ELDT) if this is your first CDL.
- Get a current medical examiner’s certificate.
- Confirm the class and endorsements you need.
- Study the commercial driver handbook.
At the DMV
- Complete the application and pay the fee.
- Pass the vision exam.
- Pass the knowledge tests to get your CLP.
- Hold the CLP at least 14 days before the skills test.
CDL endorsements at a glance
Endorsements add special cargo or passenger privileges to your license.
| Code | Endorsement | What it allows |
|---|---|---|
| H | Hazardous materials | Carrying placarded loads of hazardous materials |
| N | Tank vehicle | Driving vehicles that haul liquids or gases in tanks |
| P | Passenger | Driving a vehicle that carries passengers |
| S | School bus | Driving a school bus |
| T | Doubles and triples | Pulling more than one trailer |
Each endorsement has its own knowledge test, and some also require a skills test. The DMV lists what applies to your class on its CDL pages.
CDL numbers to memorize
General knowledge and air brake tests reward exact numbers.
Three CDL questions to try
Cover the answer, decide, then check.
What is the following distance for a 60-foot vehicle under 40 mph?
One second for each 10 feet of vehicle length.
At what pressure do spring brakes apply automatically?
The parking brake knob pops out as pressure drops.
How should you slow for a curve?
Braking in a curve can cause a skid or rollover.
A study approach that fits a work schedule
CDL study time is often squeezed between shifts. Take one quiz a day, read the explanations for every miss, and return to the handbook only for the sections that match your errors. Air brakes are the topic that most needs memorization, so drill those numbers until you can write them from memory.
Save the mock exam for the day before your test. Treat a score under 80 percent as a sign to review, not a reason to cancel. Retake it after a night of rest and compare your results.
Where CDL applicants lose points
These topics cause most of the missed questions.
Mixing up air brake numbers
Cut-in, cut-out, warning and leak limits look alike. Make a table and drill it.
Guessing following distances
The one-second-per-10-feet rule with the extra second above 40 mph is a frequent question.
Skipping inspection steps
Tread depth, wheels, springs and leaks come up in several forms.
Study guides and articles
Read a little more before you test.
CDL Classes Explained: Class A, Class B and Class C
Weight and cargo decide which commercial license you need. Here is how the three classes differ.
ReadCDL Air Brakes Test: The Numbers You Need to Memorize
The pressures and leak limits that show up again and again on CDL air brake questions.
ReadWhat Is ELDT? Entry-Level Driver Training for a CDL
Since 2022, first-time CDL applicants must complete required training before certain tests. Here is what that means.
ReadCDL practice test
Choose your state and take four free CDL permit quizzes.
ReadMore California practice tests
Keep going with another exam, or go back to the state hub.
California CDL permit test FAQ
What do I need to get a California CDL permit?
You complete an application, pay the fee, pass a vision exam and pass the knowledge tests for the class and endorsements you want. First-time applicants must also complete entry-level driver training and hold a medical certificate.
How many questions are on the CDL general knowledge test?
The test is commonly reported as 50 questions with 40 correct needed to pass, which is 80 percent. Confirm the current format with the DMV.
Do I need to take the air brakes test?
Yes, if you plan to drive a vehicle with air brakes. If you skip it or fail it, your license carries an L restriction that bars air-braked vehicles.
How long do I hold the CLP before the skills test?
At least 14 days under federal rules.
What is the alcohol limit for a commercial driver?
0.04 percent while driving a commercial vehicle, half the standard adult limit.
What is an endorsement?
An endorsement lets you drive a specific type of vehicle or cargo, such as passenger (P), school bus (S), tank (N), hazardous materials (H) or doubles and triples (T).
What is the difference between Class A, B and C?
Class A covers heavy combination vehicles, Class B covers heavy single vehicles, and Class C covers smaller vehicles that carry 16 or more people or placarded hazardous materials.
Are these questions the real CDL test?
No. They mirror the topics and style of the permit tests, but the wording is our own. Study the California Commercial Driver Handbook alongside them.
Sources: California DMV CDL information and the California driver handbooks. Check the DMV for current fees and requirements.