Transportation

CDL General KnowledgeCommercial Driver's License — General Knowledge

The CDL General Knowledge test is the foundational written exam every commercial driver's license applicant — Class A, B, and C — must pass to get a Commercial Learner's Permit. Built from the AAMVA/FMCSA model CDL manual and given by each state's DMV, it covers safe vehicle operation, inspection, space and hazard management, and cargo basics.

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Exam facts

Everything you need to know about the CDL General Knowledge exam.

Passing score
80% (typically 40 of 50)
Format & length
~50 multiple-choice questions (varies by state)
Voucher cost
Bundled into state CLP/CDL fees (~$10–$100; varies by state)
Prerequisites
Valid driver's license; 18+ intrastate / 21+ interstate; DOT medical certification
Validity
Passing earns the Commercial Learner's Permit (valid 180 days); 14-day hold before the skills test

Exam facts sourced from the official FMCSA (Commercial Driver License Program) certification page. Last reviewed June 2026.

What’s tested

Key topics on the CDL General Knowledge exam.

The Cert Climb question bank is mapped to every domain on the official CDL General Knowledge exam blueprint, so what you study is what the test asks.

Who it’s for

Built for the people taking this exam.

Aspiring commercial truck and bus drivers, and career-changers entering trucking, transit, delivery, or construction driving.

Why it matters in 2026

The career signal.

It is the required gateway for every CDL class and endorsement — you cannot start behind-the-wheel training without it. With ~3.8M active CDL holders and ~400,000 new CDLs a year plus high turnover, it is the front door to a high-demand trade.

Sample question

What a CDL General Knowledge question looks like.

What is the main reason a commercial driver performs a pre-trip inspection before every trip?

  • ATo satisfy a company paperwork requirement only
  • BTo find problems that could cause a crash or breakdown before driving
  • CTo warm up the tires for better fuel economy
  • DTo reset the vehicle's electronic logging device
See the answer & explanation

Correct: B. To find problems that could cause a crash or breakdown before driving

Why: The purpose of the pre-trip inspection is safety: catching mechanical problems before they cause a crash or a breakdown on the road.

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What you get

Everything you need to actually pass.

Full question bank

70 questions covering every objective on the official CDL General Knowledge exam blueprint, with detailed explanations on every option — right and wrong.

Quiz modes

Timed exam simulation, missed-only review, topic drills, and a daily question of the day. Practice the way you study best.

Flashcards

Spaced-repetition flashcards generated from each topic. Pull them up on a phone in the gap between meetings.

Progress tracking

See per-topic accuracy and answered counts. Find weak areas before they cost you on test day.

Per-category premium

Unlocking CDL General Knowledge unlocks every other Transportation exam in the Cert Climb catalog — pay once, stack credentials.

No-fluff explanations

Every wrong answer comes with a 2-3 sentence explanation of why it’s wrong, not just “the correct answer is X.” Pattern recognition is the whole game.

Read while you study

CDL General Knowledge articles & study guides

FAQ

Frequently asked questions about CDL General Knowledge

What is the CDL General Knowledge exam?

The CDL General Knowledge test is the foundational written exam every commercial driver's license applicant — Class A, B, and C — must pass to get a Commercial Learner's Permit. Built from the AAMVA/FMCSA model CDL manual and given by each state's DMV, it covers safe vehicle operation, inspection, space and hazard management, and cargo basics.

How many questions are on the CDL General Knowledge exam, and how long is it?

~50 multiple-choice questions (varies by state)

What is the passing score for the CDL General Knowledge exam?

80% (typically 40 of 50)

How much does the CDL General Knowledge exam cost?

Bundled into state CLP/CDL fees (~$10–$100; varies by state)

Are there prerequisites for the CDL General Knowledge exam?

Valid driver's license; 18+ intrastate / 21+ interstate; DOT medical certification

How long is the CDL General Knowledge certification valid?

Passing earns the Commercial Learner's Permit (valid 180 days); 14-day hold before the skills test

How many questions does the CDL General Knowledge bank have?

70 questions, organized into 8 subject areas mapped to the official exam objectives.

Is the free trial really free?

Yes. 30 questions, no credit card, no email-trap, no “activate by Friday or pay” spam. You either upgrade because the bank’s good, or you don’t.

What does premium cost?

Premium is sold per category and unlocks every Transportation exam in the Cert Climb catalog. Plans are 1-month, 3-month, or 12-month — see the upgrade modal for current pricing.

How current is the CDL General Knowledge content?

We track exam version updates and refresh the bank within weeks of new objectives. Where the version of an exam matters (e.g. CompTIA SY0-701 vs. SY0-601), question explanations call it out.

Can I cancel my subscription anytime?

Yes. Cancellation is one click from your profile. Your access continues through the end of the period you’ve already paid for.

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30 free questions on CDL General Knowledge — no card, no commitment.

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