How many questions are on the Ohio CDL knowledge test?

The Ohio CDL general knowledge test has 50 multiple-choice questions, and you need 80% (40 correct) to pass. Each endorsement test like General Knowledge is shorter (typically 20-30 questions) but uses the same 80% threshold.

What's the minimum age for a CDL in Ohio?

In Ohio, the minimum age for a CDL is 18 (intrastate); 21 (interstate). Federal law requires drivers to be 21+ to drive a CMV across state lines or to transport hazardous materials, regardless of state minimum age.

Do I have to pass the General Knowledge test before any other CDL test?

Yes. The General Knowledge test is the gateway test for the CDL. You must pass it before you can take any endorsement tests (HazMat, Tanker, Passenger, School Bus, Doubles/Triples) or class-specific tests (Combination Vehicles for Class A). Once you pass General Knowledge, you receive a CDL learner's permit and can begin behind-the-wheel practice and additional knowledge tests.

How many questions are on the CDL General Knowledge test?

Most states use 50 multiple-choice questions for the General Knowledge test, but a handful of states use slightly different counts. You need 80% to pass in every state. Check your state's CDL manual or our state-specific page for the exact number of questions in your state.

Can I take the General Knowledge test online?

A few states allow CDL knowledge tests online, but most still require in-person testing at a DMV testing center to verify identity and prevent cheating. Check with your state DMV before assuming an online option is available.

How is the CDL General Knowledge test different from the regular driver's license test?

The CDL General Knowledge test focuses on heavy commercial vehicles, their longer braking distances, blind spots, hours-of-service rules, cargo securement, and the federal regulations that apply to interstate commerce. The regular driver's license test covers passenger cars and basic road rules. Even experienced drivers find the CDL General Knowledge content significantly different and broader than the standard driver test.

Do I need to retake the General Knowledge test if my CDL expires?

Each state sets its own rules. If your CDL has been expired for a short period (typically under a year), most states allow a straightforward renewal without re-testing. If your CDL has been expired for several years, your state may require you to retake the General Knowledge test and possibly the skills test. Always check with your state DMV for current rules.

Ohio CDL general knowledge practice test

Updated for 2026 · 163 general knowledge questions of 443 across the full OH CDL path · Aligned to the commercial driver manual · Part of the OH CDL path

Foundation for every CDL. Covers federal rules, road safety, and vehicle handling.

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4 tests, each drawing from a different question pool. Take all 4 to cover the full 163 questions.

Quick test

25 random questions from the general knowledge pool. Try it free.

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Practice test 2

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25 fresh questions, sample 2 of the general knowledge pool. No overlap with the Quick Test or other Practice Tests.

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Practice test 3

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25 fresh questions, sample 3 of the general knowledge pool. No overlap with the Quick Test or other Practice Tests.

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Full coverage

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50 questions covering the full general knowledge bank. Take when you're ready for everything.

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Drill 50 General Knowledge Questions

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Drill every question in this section with full explanations.

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OH CDL Study path

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About the Ohio General Knowledge test

The General Knowledge test has 50 multiple-choice questions in most states (some states use a slightly different question count). You need an 80% score to pass. Topics include safe driving practices, transporting cargo safely, vehicle inspection procedures, communication with other drivers, speed and space management, hazard awareness, distracted-driving rules, fatigue and hours of service basics, accident procedures, and the consequences of alcohol and controlled substance use. The test draws from the General Knowledge section of your state's CDL manual. In Ohio, this test is administered by the BMV as part of the standard CDL knowledge exam - review the Ohio CDL manual section on general knowledge for the most accurate state-specific content.