Iowa CDL practice test

Getting a commercial driver's licence in Iowa starts with the CDL knowledge tests. The content is federal: every state, Iowa included, writes its tests from the FMCSA CDL manual, so the general knowledge test has 50 questions, the endorsement tests have 20 to 30, and the passing score is 80% on each. Iowa Department of Transportation administers the test; the rules behind it are published by the FMCSA. Try the free Iowa CDL practice questions below, then pick a full test.

50general knowledge questions
80%passing score on every test
8knowledge tests covered
IApick your state once in the app

Free Iowa CDL practice quiz

Five questions from the general knowledge, air brakes and combination vehicles banks, the three tests most Iowa Class A applicants take first. Tap an answer to see if you were right and read the explanation.

0 of 5 right0 of 5 answered

If there are two left-turn lanes at an intersection, which one should you use?
When making a left turn, you should begin the turn:
Because of your vehicle's size and weight, when crossing or entering traffic you should remember that:
In the CDL manual, a 'hazard' is:
Which of these is a clue that a parked car may be about to pull into your path?

Every CDL test for Iowa drivers

Each page has a free ten-question quiz, the real question count, the 80% pass mark and what the test covers.

How the Iowa CDL knowledge test works

You take the general knowledge test first; it is required for every CDL class. Class A drivers add the combination vehicles test. Almost everyone takes the air brakes test, because skipping it puts an air brake restriction on the licence. Endorsements (hazmat, tanker, doubles/triples, passenger, school bus) each have their own knowledge test. Pass the tests and you hold a commercial learner's permit; the skills test in a truck comes later.

Fees, appointment rules and test centre locations are set by Iowa; the current ones from Iowa DOT are in the next section. What does not change is the content, and that is what PassRig drills.

Iowa CDL fees and rules

In Iowa the CDL is issued by the Iowa Department of Transportation. The figures below are taken from its own pages and were last checked on 2 November 2026. Fees and rules change, so confirm with the agency before you go.

Study from the state's own book: Iowa CDL Manual. PassRig's questions are written from the same FMCSA manual it is based on.

What	IA	Source
Learner's permit fee	$12	iowadot.gov
CDL fee	$8 per year for an 8-year licence	iowadot.gov
Permit valid for	1 year, no renewal	iowadot.gov
Minimum age	18; 21 to drive interstate	iowadot.gov
Appointment	Make an appointment at a DMV location	iowadot.gov
Medical certificate	Must certify type of CMV use; a medical certificate may be required	iowadot.gov
Entry-level driver training	Required; Iowa DOT confirms completion before giving CDL tests	iowadot.gov
Also worth knowing	CLP must be held at least 14 days before the skills and drive test	iowadot.gov

4 official pages from Iowa DOT were read for this section. Nothing on it is estimated.

Iowa CDL test questions

How many questions are on the Iowa CDL test?

The Iowa CDL general knowledge test follows the federal model: 50 questions, 40 correct to pass. Endorsement tests are shorter: air brakes 25, hazmat 30, and combination vehicles, tanker, doubles/triples, passenger and school bus 20 each.

What is the passing score on the Iowa CDL permit test?

80% on every knowledge test, the same pass mark used across the United States.

Where do I take the CDL knowledge test in Iowa?

Iowa Department of Transportation gives the test. Make an appointment at a DMV location The test content itself comes from the FMCSA CDL manual.

How much does a CDL permit cost in Iowa?

Iowa DOT lists the commercial learner's permit fee as $12. Fees change, so check the agency's fee page before you go.

Does PassRig have Iowa CDL practice questions?

Yes. Pick Iowa in the app and you get practice sets and mock exams built from the knowledge test content your state uses, with the real counts and the 80% line.