Ohio CDL Test Questions 2026: What Each Test Covers

Ohio BMV requires a knowledge test for each applicable vehicle class, each endorsement, and removal of an air-brake restriction. The current BMV CDL page does not publish a simple official question-count table for every CDL knowledge test, so this guide focuses on the tests and subject areas the state actually directs applicants to study instead of presenting third-party counts as official.

Use the Current Ohio CDL Manual

Ohio BMV directs applicants to the current Commercial Driver License Manual, HSY 7605. That manual should be the primary study source because it covers the federal CDL knowledge areas together with Ohio’s licensing and testing information. Practice questions are useful for recall, but they should reinforce the manual rather than replace it.

General Knowledge

General Knowledge is the foundation for CDL applicants. Study safe vehicle operation, inspections, basic control, shifting and communication, speed and space management, hazards, emergencies, cargo basics, and other core commercial-driving concepts in the Ohio manual.

Air Brakes

If the vehicle you plan to operate uses air brakes and you want to avoid an air-brake restriction, study the air-brake section carefully. Key concepts include system components, dual-air systems, warning devices, spring/parking brakes, inspections, brake lag, stopping, and safe use on grades.

Combination Vehicles

Class A applicants operating combination vehicles should study coupling and uncoupling, combination-vehicle inspections, preventing rollover and jackknife situations, handling trailers, air lines, and safe operation of tractor-trailer combinations.

Endorsement Tests

Additional knowledge tests apply when you seek endorsements such as tanker, doubles/triples, passenger, school bus, or hazardous materials. HazMat has additional federal security and ELDT-related requirements beyond simply studying for the knowledge test.

Where You Take the Tests

Ohio BMV directs applicants to a Driver Exam station for CDL knowledge testing. After meeting the knowledge requirements, the CLP is issued through a Deputy Registrar. That location distinction is important because older Ohio guides sometimes direct applicants to the wrong office for the written tests.

About Question Counts and Passing Scores

Many third-party practice sites publish fixed question counts for General Knowledge, Air Brakes, and Combination Vehicles. Unless a count is confirmed in a current Ohio BMV source for the exact test, treat it as preparation guidance rather than an official 2026 guarantee. Test design can change, while the safest study strategy—mastering the current Ohio CDL manual—does not.

Retesting

Ohio BMV’s current CDL page provides a specific two-day wait when a portion of the skills test is failed. It does not present the same simple statewide retest statement for every knowledge-test scenario on that page. If you fail a knowledge test, ask the Driver Exam station for the current retest timing and fee that applies to your transaction.

Frequently Asked Questions

How many questions are on the Ohio General Knowledge CDL test?

FastLessonHub does not label a third-party count as official unless it is supported by a current Ohio BMV source. Prepare from the current manual and verify test-specific details with the Driver Exam station.

Is there one CDL knowledge test for every applicant?

No. Ohio requires knowledge testing for the applicable CDL class and for endorsements or restriction removals that apply to the credential you want.

Can practice tests replace the Ohio manual?

No. Use practice tests to check your recall, but use the current Ohio CDL manual as the authoritative study base.

Sources: Ohio Bureau of Motor Vehicles CDL Application Eligibility and CDL Testing; Ohio Commercial Driver License Manual HSY 7605. Last verified October 2026.

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