Try 10 free Iowa CDL questions
Real General Knowledge questions from the same bank our students use. No account, no email needed. You see the correct answer after each question, and your score at the end.
- 10 questions, from the 81-question General Knowledge bank, one for each key manual topic
- Practice mode: the correct answer and manual reference show after each question
- 80% is a pass, the same standard as the real Iowa CDL knowledge test
Takes about 3 minutes. Keyboard: A to D to answer, Enter for next.
About the Iowa CDL knowledge test
The General Knowledge test is the written exam every CDL applicant sits, whatever class of license they are working toward. The questions come from the Iowa CDL manual, they are multiple choice, and you need 80% to pass. Iowa Department of Transportation gives the test, and passing it is what earns your commercial learner's permit, the permit you hold before taking the skills test in a truck.
What it covers
Our 10 free questions and the full 81-question General Knowledge bank are drawn from these manual sections:
- Vehicle Inspection
- Basic Control of Your Vehicle
- Shifting Gears
- Seeing
- Communicating
- Controlling Speed
- Managing Space
- Seeing Hazards
Endorsements such as HazMat, Tank, Passenger and School Bus are separate written tests on top of this one. See which Iowa CDL endorsements you need before you book anything, because the endorsement you are missing decides which tests you sit.
What Iowa requires
- The CLP must be held at least 14 days and ELDT completed before the skills test.
- Adding an endorsement outside your renewal period costs $10 for a new card.
- Licenses for drivers 78 and older are issued for two years instead of eight.
- Third-party testers may require you to enroll in their training program to test with them.
Checked against Iowa Department of Transportation on September 16, 2026. Rules change, so confirm anything that affects your booking before you travel.
Where to go next
Work out which license class you need, then study the test that goes with it:
- Iowa CDL classes: what Class A, B and C each let you drive.
- Iowa CDL endorsements: H, N, P, S, T and X, and who needs each.
- Iowa CDL study material: the full study guides, practice tests and narrated audio.
Common questions
What score do I need to pass the Iowa CDL knowledge test?
You need 80% to pass. Miss more than that and you retake the test, so the goal while studying is to be comfortably above 80%, not just at it.
Where do I take the Iowa CDL knowledge test?
At Iowa Department of Transportation. Passing the General Knowledge test is what earns your commercial learner's permit, which you hold before the skills test.
Is this free test the real Iowa CDL exam?
No. These are 10 real questions from the same General Knowledge bank our paid study material uses, so the style and difficulty match what you are studying for. The official exam is given only by Iowa Department of Transportation.