Iowa CDL Practice Tests

Prepare for your IA Commercial Driver's License exam with our comprehensive practice tests. All tests are based on the official Iowa CDL handbook and FMCSA regulations.

Available Practice Tests

Choose a practice test below to begin studying for your Iowa CDL exam.

General Knowledge Test

Master the fundamental CDL knowledge covering safe driving practices, traffic laws, and vehicle operation.

  • 50 questions
  • 40/50 to pass
  • 60 minutes
Start Test

Air Brakes Test

Learn about air brake systems, operation, and safety procedures required for commercial vehicles.

  • 25 questions
  • 20/25 to pass
  • 30 minutes
Start Test

Combination Vehicles Test

Prepare for operating combination vehicles including tractor-trailers and understanding coupling procedures.

  • 20 questions
  • 16/20 to pass
  • 25 minutes
Start Test

Hazardous Materials Test

Study hazardous materials regulations, placarding requirements, and safe handling procedures.

  • 30 questions
  • 24/30 to pass
  • 40 minutes
Start Test

Tanker Vehicles Test

Understand liquid surge, proper loading, and safety procedures for operating tanker vehicles.

  • 20 questions
  • 16/20 to pass
  • 25 minutes
Start Test

Passenger Transport Test

Learn passenger safety, vehicle operation, and regulations for transporting people commercially.

  • 20 questions
  • 16/20 to pass
  • 25 minutes
Start Test

School Bus Test

Study specialized knowledge for safely transporting school children including loading and unloading.

  • 20 questions
  • 16/20 to pass
  • 25 minutes
Start Test

Doubles and Triples Test

Master the skills for operating double and triple trailer combinations safely and legally.

  • 20 questions
  • 16/20 to pass
  • 25 minutes
Start Test

Iowa CDL Testing Requirements

To obtain a Commercial Driver's License (CDL) in Iowa, you must pass both knowledge tests and skills tests. Our practice tests help you prepare for the knowledge portion of the exam.

Knowledge Test Requirements

  • General Knowledge Test: Required for all CDL applicants
  • Endorsement Tests: Additional tests required for specific vehicle types or cargo
  • Air Brakes Test: Required if your vehicle has air brakes
  • Combination Vehicles: Required for Class A CDL

About Iowa CDL Testing

The Iowa CDL knowledge tests are administered by the Iowa Department of Transportation – Motor Vehicle Division. Each test consists of multiple-choice questions based on the information in the Iowa CDL handbook.

To pass each test, you must achieve the minimum passing score. We recommend taking multiple practice tests until you consistently score above the passing threshold.

Study Tips for Iowa CDL Tests

  • Read the official Iowa CDL handbook thoroughly
  • Take practice tests multiple times to identify weak areas
  • Review explanations for questions you miss
  • Focus on Iowa-specific regulations and requirements
  • Understand federal FMCSA regulations that apply nationwide
  • Practice until you consistently score above the passing threshold

Iowa DMV Information

Iowa Department of Transportation – Motor Vehicle Division

Visit IA DMV Website
Official Resources
Need Help?

Contact the IA DMV for official information about CDL testing requirements, scheduling, and fees.

Contact IA DMV