The CDL Permit Test

For CDL students

Updated September 28, 2026

This guide covers which knowledge tests you take, how many questions are on each, what score you need, and how to study. Every rule comes from the federal CDL rules or a state licensing agency. There are no made-up practice questions here.

Which CDL Knowledge Tests You Take

Which tests you take depends on the class of license you want and the endorsements you add. Here is the lineup most Class A drivers face:

1. EveryoneGeneral knowledgeTaken for Class A, B and C
2. Class ACombination vehiclesFail it and you cannot get a Class A permit
3. Air brakesAir brakesSkip or fail it and you get an air brake restriction

Each endorsement you want adds a knowledge test of its own:

• Doubles and triples (T): knowledge test only
• Tank vehicle (N): knowledge test only
• Hazardous materials (H): knowledge test, plus a TSA background check, and entry-level training first if it is your first hazmat endorsement
• Passenger (P) and school bus (S): knowledge test, plus a skills test later

Want the details on each endorsement? See our guide to CDL endorsements. Not sure which class you need? Read Class A vs Class B CDL.

How Many Questions Are on the CDL Permit Test?

Federal rules set the passing score: at least 80% on each test. They do not set one question count for the whole country. Each state builds its tests from a question pool approved by FMCSA, and each test must include a set number of questions from each subject.

So the count depends on your state. Here is Washington’s table, as its Department of Licensing posts it:

For a Class A with air brakes in Washington, that adds up to 95 questions across three tests. Your state may differ, so check its CDL page before test day.

The General Knowledge Test

Every CDL applicant takes this test, for Class A, B or C. Federal rules list 20 areas every driver must know. They include:

• Safety rules for inspections, hours and cargo
• Vehicle controls, shifting, backing and turning
• Seeing, signaling and managing speed and space
• Night driving, bad weather, hazards and emergencies
• How alcohol, drugs and fatigue affect driving
• Vehicle inspections and cargo loading

Virginia’s DMV tells Class A, B and C drivers to study section 2 (driving safely) and section 3 (transporting cargo safely) of the state manual for this test.

The Combination Vehicles Test

This is the extra test for a Class A. It covers what makes a rig with a trailer different: rollover risk, coupling and uncoupling, and checking the connections between the units. It comes from section 6 of the manual.

It matters more than most drivers think. Federal rules say that if you score under 80% on the combination test, the state must not issue you a Class A permit or license.

The Air Brakes Test

You take the air brakes test if your truck has air brakes, including air over hydraulic brakes. It comes from section 5 of the manual.

If you fail it, or skip it, you can still get a permit. But the state must mark it with a restriction that bars you from driving any vehicle with air brakes. Florida’s licensing agency notes that most Class A vehicles have air brakes, so most Class A students take this test.

How to Study for the CDL Permit Test

Study your own state’s CDL manual. Virginia’s DMV says its questions come from the Virginia Commercial Driver’s Manual. Washington’s DOL says its guide contains all the information you need to pass.

Each manual follows the same national model, so the section numbers line up from state to state:

Find your state’s official manual on our CDL manual by state page. A few study tips that follow from the rules:

• Read the sections for your tests, not the whole book at once. The manual’s first section has a table that shows which to study.
• Do not memorize answers. States must switch to a different version of the test when you retake one, and at least 25% of the questions change from one version to the next.
• Use your agency’s own sample test if it has one. California’s DMV and Washington’s DOL both post one.

After You Pass: Your CDL Permit

Pass your tests, and your state issues a commercial learner’s permit (CLP). Here is what federal rules say about it:

1. You drive with a CDL holder beside you. The CDL holder must have the right class and sit in the front seat next to you.
2. You wait at least 14 days. You cannot take the skills test in the first 14 days after your CLP is first issued.
3. You finish entry-level training. First-time Class A and B drivers must train with a provider on FMCSA’s registry before the skills test.
4. You take the skills test within a year. A CLP lasts no more than one year from the day it was first issued. After that, you retake the knowledge tests.

Only three endorsements can go on a CLP: passenger, school bus and tank (empty tanks only). You cannot haul hazmat on a permit. For test day, read our guide to the CDL skills test. For the full timeline, see how long it takes to get a CDL.

Sources

Last checked September 28, 2026. Question counts and rules change. Check with your state’s licensing agency before test day. This guide is a plain-language summary, not legal advice.

1. 49 CFR 383.133, test methods
2. 49 CFR 383.135, passing scores
3. 49 CFR 383.111, required knowledge
4. 49 CFR 383.93, endorsements
5. 49 CFR 383.95, restrictions
6. 49 CFR 383.25, commercial learner’s permit
7. 49 CFR 380.609, entry-level driver training
8. FMCSA, CDL drivers page
9. Washington DOL, CDL knowledge test
10. Virginia DMV, CDL knowledge exams
11. California DMV, sample commercial drivers written test
12. Florida HSMV, commercial driver license
13. Colorado DMV, CDL general information and manual DR 2251 (June 2023)