Free Idaho CDL Practice Test (2026)
Practice the Idaho CDL permit test the way it is really written, with the correct answer and an explanation on every question.
Idaho CDL Requirements
5-Question ID Challenge
Real general knowledge questions, with the answer and an explanation after each one.
What is the very first thing you should do if a front tire blows out while driving at highway speeds?
Idaho CDL permit test: what to expect
The written exam most people call the Idaho CDL permit test is the general knowledge test, and passing it is what gets you a commercial learner's permit rather than the license itself. You need 80% to pass, a federal standard that is the same in every state. The number of questions is set by Idaho, and our practice tests use the common 50-question format.
Once you hold the permit you have to keep it for at least 14 days before you are allowed to attempt the skills test, so it is worth sitting the written exam as early as you can. Practice below until you are clearing Idaho's standard comfortably rather than scraping it.
How to get a CDL in Idaho
To obtain a Commercial Driver's License in the Idaho, you must first pass the General Knowledge exam. Depending on the type of vehicle you intend to drive, additional endorsements like Air Brakes, Tanker, or Hazmat may be required.
- Get a DOT physical, then self-certify your driving category (interstate or intrastate) with the Idaho DMV and provide proof of your medical card.
- Study the Idaho CDL Driver's Handbook, then pass the General Knowledge written test (plus any endorsement tests you need) at your county DMV office. You need at least 80% to pass, and each written test costs $5.
- Receive your Commercial Learner's Permit (CLP). Idaho and federal rules require you to hold it for at least 14 days before you can take the skills test.
- Practice with a licensed CDL holder, then schedule and pass the three-part skills test: pre-trip inspection, basic vehicle control, and the on-road driving test. The skills test fee is $10.
- Pay your CDL license fee at the county DMV to be issued your Idaho commercial driver's license.
Test fees: $5 per written test, $10 skills test. Official source: Idaho Transportation Department (ITD).
Practice every part of the Idaho CDL test
Your Idaho exam is split into separate knowledge tests. Drill each one until you're confident.
5 Idaho CDL Practice Questions and Answers
Here are 5 sample Idaho general knowledge questions with the right answer and a quick explanation for each. Read through them, then take the quiz above to see how you do without looking.
1. What is the very first thing you should do if a front tire blows out while driving at highway speeds?
- A. Slam on the brakes immediately to stop the vehicle.
- B. Grip the steering wheel firmly with both hands and stay off the brakes. (correct answer)
- C. Turn sharply onto the shoulder of the road.
- D. Accelerate slightly to keep the vehicle moving straight.
Why: If a front tire fails, the vehicle will pull strongly to the side of the blown tire. You must grip the steering wheel firmly and stay off the brakes until the vehicle slows down, as braking can cause loss of control.
2. What is black ice?
- A. Thick chunks of ice that form exclusively on bridges.
- B. A thin layer of clear ice that makes the road look wet. (correct answer)
- C. Ice that forms solely from diesel exhaust.
- D. Snow that has been plowed into dark piles on the shoulder.
Why: Black ice is a thin layer of ice clear enough that you can see the road underneath it. It makes the road look wet and is incredibly slippery and dangerous.
3. If you check your tires in hot weather and the air pressure is too high, what should you do?
- A. Let enough air out to reach the recommended cold pressure.
- B. Do nothing and continue driving at normal speeds.
- C. Stop driving and wait until the tires cool down. (correct answer)
- D. Pour cold water on the tires to cool them rapidly.
Why: You should stop and let the tires cool. Never let air out of hot tires, because when they cool down, the pressure will be too low.
4. If you have to stop on the shoulder of the road at night, what should you do immediately to warn other drivers before placing your triangles?
- A. Turn off all your lights to avoid blinding them.
- B. Turn on your four-way emergency flashers. (correct answer)
- C. Honk your horn repeatedly.
- D. Shine a flashlight at oncoming traffic.
Why: You must turn on your four-way emergency flashers immediately to warn other drivers that your vehicle is stopped, while you prepare to place your warning devices.
5. Why does the CDL manual recommend turning on your turn signal well in advance of a lane change or turn?
- A. It gives the signal flasher time to warm up.
- B. It complies with maximum speed laws.
- C. Commercial vehicles take longer to maneuver, and early signaling gives other drivers more time to adjust their speed and position. (correct answer)
- D. It automatically adjusts the trailer's braking system.
Why: Early communication is key. It gives trailing and surrounding vehicles ample time to process your intentions and create space for your large, slow-maneuvering vehicle.
CDL Job Market in Idaho
Idaho is a great state if you're into agricultural and refrigerated freight. The Boise metro is one of the fastest-growing distribution markets in the Mountain West, with new warehouse space opening up regularly for retail, grocery, and e-commerce. When potato harvest hits on the Snake River Plain, reefer and flatbed rates jump, and experienced Idaho drivers plan their schedules around that peak.
Simplot Company (potato/ag), Lamb Weston, Sysco Idaho, URM Stores
Idaho CDL average: about $51,000 in 2026. The state's huge farm output (it's the world's largest potato producer) and the fast-growing Boise distribution scene keep reefer and flatbed drivers busy.
Idaho CDL Test FAQs
How old do you have to be to get a CDL in Idaho?
You must be at least 18 to drive a commercial vehicle within Idaho (intrastate). To drive across state lines (interstate) or haul hazardous materials, you must be at least 21.
What score do you need to pass the Idaho CDL knowledge test?
You need at least 80% on each written test at an Idaho DMV office. Our free Idaho CDL practice tests use the same question format, so you'll walk in ready to clear that mark.
How much does the Idaho CDL test cost?
Each written knowledge test is $5 and the skills (road) test is $10, collected at your county DMV, plus the CDL license fee when your license is issued. If you fail a written test you can retake it after three days for another $5.
How long do I have to hold my Idaho commercial learner's permit (CLP)?
Idaho and federal rules require you to hold your CLP for at least 14 days before you're allowed to take the CDL skills test.
How many questions are on the Idaho CDL general knowledge test, and how long is it valid?
The General Knowledge test is required of every new CDL applicant and follows the standard 50-question format. A passing result stays valid for one year, so plan to finish your skills test within that window.