How to Practise for the CDL Knowledge Tests with Practice Quizzes

Short answer. To get a commercial driver's license, you pass one or more knowledge tests to get a commercial learner's permit (CLP), then a three-part skills test. Federal rules set the minimum standard: at least 80% correct on every knowledge test. Each state writes and gives its own tests. That means your state's CDL manual is the best study source, and quizzing yourself section by section from that manual is the most direct way to prepare.

Checked against FMCSA on 24 September 2026. Requirements vary by state, so always confirm with your state's licensing agency.

CDL testing at a glance

Knowledge tests (for the CLP):

Skills test (for the CDL itself), in three parts:

States also require entry-level driver training for many applicants before the skills test. Check your state's current rules.

What this means for how you practise

The manual is the syllabus. State knowledge tests are built from the material in the state's CDL manual. Quiz yourself from the manual itself, not from general trucking content.

80% on every test. You cannot make up for a weak section elsewhere. Each knowledge test must be passed on its own.

Endorsement tests are separate. Study each endorsement section as its own unit and quiz on it separately.

The pre-trip inspection is a memorised routine. You need to be able to name components and what you check on each. That suits flashcards and quick recall quizzes.

Why self-quizzing works for the knowledge tests

Knowledge tests reward precise recall of rules, numbers and procedures. Practice testing beats rereading for long-term retention (Roediger and Karpicke, 2006), and spreading your reviews over days helps more than cramming (Cepeda et al., 2006).

A 3-week knowledge-test practice plan

Days 1–2: download your state's current CDL manual. List the sections you need: general knowledge plus your vehicle class and endorsements.

Days 3–14: one manual section per day.

Days 15–18: mixed quizzes across all the sections you need, aiming well above 80% before you book the test.

Days 19–21: review flashcards only, then take the test.

For the skills test, practise the pre-trip inspection out loud, using your state's checklist, until you can say the whole routine from memory.

How to build CDL practice sets with SimpleQuizMaker

Building quizzes from your own state's manual keeps the questions tied to the rules you will actually be tested on. See the CDL exam page and the quiz maker for truck drivers.

Worked example: turning a manual section into a quiz

Say today's section is the air brakes chapter of your state manual.

Working from the manual's own text means your quiz uses the same figures and wording as your state's test.

Common mistakes on CDL knowledge tests

Test-day checklist

Frequently Asked Questions

How many questions are on the CDL general knowledge test?

Federal rules require at least 30 items. States write their own tests, and many use more. Your state's licensing agency can tell you the exact number.

What score do I need to pass a CDL knowledge test?

At least 80% correct on each knowledge test, under the federal minimum standard.

What are the three parts of the CDL skills test?

The vehicle inspection (pre-trip), basic vehicle control, and the on-road driving test.

Do I need an endorsement test?

Only if you will drive a vehicle or carry a load that requires one, such as hazardous materials, tank vehicles, passengers or school buses. Each endorsement has its own knowledge test.

Is the CDL test the same in every state?

No. Federal rules set minimum standards, and each state develops and gives its own tests. Study from your state's current CDL manual.

Are AI-generated CDL questions official?

No. They are practice questions written by an AI from the text you provide. Building them from your state's manual keeps them close to the real rules, but only the state test counts.

Keep going

Sources

Sources: FMCSA: how do I get a Commercial Driver's License? · eCFR: 49 CFR Part 383, Subpart H (Tests) · FMCSA: Commercial Driver's License program. Checked 24 September 2026.

*SimpleQuizMaker is not affiliated with or endorsed by FMCSA, the U.S. Department of Transportation, or any state licensing agency. Quizzes described here are AI-generated practice, not official CDL test questions.*

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