The CDL exam starts with written knowledge tests at your state DMV to get a commercial learner’s permit (CLP), followed by a skills test. You also need a valid DOT physical medical certificate.
Practice on the free CDL practice test.
Key takeaways
- Federal rules require 80% to pass each knowledge test.
- Most states’ General Knowledge test has 50 questions (40 correct to pass).
- Add tests for air brakes, combination vehicles and endorsements (hazmat, tanker, passenger, school bus).
- The skills test includes a vehicle inspection, basic control and a road test.
USA CDL Exam: Quick Facts
- Passing
- 80% on each knowledge test
- General Knowledge
- Usually 50 questions
- Required
- DOT medical certificate
- Skills test
- Inspection, basic control, road
CDL Knowledge Tests
- General Knowledge (all applicants)
- Air Brakes
- Combination Vehicles (Class A)
- Endorsements: Hazardous Materials (H), Tank (N), Doubles/Triples (T), Passenger (P), School Bus (S)
Since 2022, first-time Class A and B applicants must also complete federal Entry-Level Driver Training (ELDT) before the skills test (and before the hazmat knowledge test).
More on CDL Knowledge Tests →Free practice test
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Go to the USA CDL Exam practice test →USA CDL Exam FAQs
How many questions are on the CDL general knowledge test?
Most states use 50 questions; federal rules require at least 30 and a score of 80%.
Full answer →Do I need a DOT physical for a CDL?
Yes. Most interstate drivers need a current medical examiner’s certificate.
Full answer →Official sources
Disclaimer: This guide is for general information. Rules, fees and procedures can change. Confirm the current requirements with the official agency listed in the sources. Read our editorial policy.