Free Idaho CDL Practice Test — Updated for 2025

Getting your Commercial Driver’s License in Idaho starts with the written knowledge tests. This page gives you free, simple 18Idaho CDL practice tests for every major section: 18General Knowledge, Air Brakes, Combination Vehicles, Hazmat, Passenger, School Bus, Tankers, and Doubles/Triples. You’ll see one question at a time, get instant feedback, and short explanations to help you learn faster and pass with confidence.

Idaho CDL at a Glance (Plain-English Summary)

  • Age & eligibility:
    18+ for intrastate (within Idaho), 21 to drive interstate, carry hazmat or transport passengers.
  • Valid license & record:
    You need a valid Hawaii driver’s license and a clean record.
  • Medical card:
    Most CDL drivers must keep a current DOT Medical Examiner’s Certificate and self-certify their driving type.
  • CLP:
    Pass the written tests for your vehicle class (A/B/C) and any neededendorsements to get a Commercial Learner’s Permit (CLP).
  • ELDT:
    Entry‑Level Driver Training is require for the Class A/B and for H, S, P endorsements before the skills test.
  • Skills test:
    After holding your CLP for at least 14 days take the three-part skills test (pre‑trip, basic control, road).
  • Hazmat note:
    Hazmat (H) also requires a TSA background check and a Hazmat knowledge test.
  • Where to test:
    Knowledge and skills tests are handled by the county DMV offices (Honolulu, Maui, Hawaii, Kauai) under the Hawaii Department of Transportation (HDOT). Check current steps, fees, and locations with your county DMV
  • Tip:
    Rules and fees can change. Always confirm the latest requirements with HDOT or your local DMV before you schedule.

What’s on the Idaho CDL Knowledge Tests

General Knowledge

— vehicle inspection, safe driving, space/speed management, night & weather driving, distracted and drowsy driving, emergencies, rail crossings, and sharing the road.

Air Brakes

— system parts, dual-air setups, spring brakes, proper braking, stopping distance, and downhill control.

Combination Vehicles

— coupling, jackknife prevention, rollovers, following distance, and backing safely.

Hazardous Materials (H)

— classes, placards, papers, loading/unloading, segregation, emergency response, and TSA check.

Passenger (P) & School Bus (S)

— loading/unloading, safety procedures, emergency exits, rail crossings, and passenger control.

Tankers (N)

— surge/slosh, rollover control, curve speeds, and safe starts/stops.

Doubles/Triples (T)

— coupling order, trailer checks, rollover/off-tracking awareness.

Pre‑Trip Inspection

— engine, suspension, brakes, tires/wheels, lights, coupling, in-cab checks, and emergency gear.

Required for All CDL Drivers

These tests are mandatory for all Commercial Driver's License applicants

About General Knowledge Tests

Basic rules, regulations, and safe driving practices for commercial vehicles

General Knowledge Test 1

Basic CDL knowledge and traffic laws

📝 50 Questions 🎯 80% to pass
Start Test

General Knowledge Test 2

Vehicle safety and inspection procedures

📝 50 Questions 🎯 80% to pass
Start Test

General Knowledge Test 3

Driving techniques and hazard awareness

📝 50 Questions 🎯 80% to pass
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General Knowledge Test 4

Transportation of cargo and passengers

📝 50 Questions 🎯 80% to pass
Start Test

General Knowledge Test 5

Emergency procedures and vehicle maintenance

📝 50 Questions 🎯 80% to pass
Start Test

General Knowledge Test 6

Final comprehensive review test

📝 50 Questions 🎯 80% to pass
Start Test
About Air Brakes Tests

Air brake systems, inspection, and operation procedures

Air Brakes Test 1

Basic air brake system components and operation

📝 25 Questions 🎯 80% to pass
Start Test

Air Brakes Test 2

Air brake inspection and testing procedures

📝 25 Questions 🎯 80% to pass
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Air Brakes Test 3

Emergency procedures and troubleshooting

📝 25 Questions 🎯 80% to pass
Start Test

Air Brakes Test 4

Advanced air brake systems and safety

📝 25 Questions 🎯 80% to pass
Start Test
About Pre-Trip Inspection Tests

Vehicle inspection procedures and safety checks

Pre-Trip Inspection Test 1

Engine compartment and cab inspection

📝 20 Questions 🎯 80% to pass
Start Test

Pre-Trip Inspection Test 2

Exterior vehicle inspection

📝 20 Questions 🎯 80% to pass
Start Test

Pre-Trip Inspection Test 3

Trailer and coupling system inspection

📝 20 Questions 🎯 80% to pass
Start Test

Endorsement Tests

Additional certifications for specialized commercial driving

About Combination Vehicles Tests

Tractor-trailers, truck and trailer combinations

Combination Vehicles Test 1

Coupling and uncoupling procedures

📝 20 Questions 🎯 80% to pass
Start Test

Combination Vehicles Test 2

Inspection of combination vehicles

📝 20 Questions 🎯 80% to pass
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Combination Vehicles Test 3

Driving combination vehicles safely

📝 20 Questions 🎯 80% to pass
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Combination Vehicles Test 4

Backing and maneuvering techniques

📝 20 Questions 🎯 80% to pass
Start Test

Combination Vehicles Test 5

Advanced combination vehicle operation

📝 20 Questions 🎯 80% to pass
Start Test
About Hazmat Tests

Hazardous materials transportation and safety

Hazmat Test 1

Hazmat classification and identification

📝 30 Questions 🎯 80% to pass
Start Test

Hazmat Test 2

Loading and handling procedures

📝 30 Questions 🎯 80% to pass
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Hazmat Test 3

Documentation and placarding

📝 30 Questions 🎯 80% to pass
Start Test

Hazmat Test 4

Emergency response and safety procedures

📝 30 Questions 🎯 80% to pass
Start Test
About Passenger Vehicles Tests

Buses and vehicles designed to transport passengers

Passenger Vehicle Test 1

Pre-trip inspection for passenger vehicles

📝 20 Questions 🎯 80% to pass
Start Test

Passenger Vehicle Test 2

Loading and unloading passengers

📝 20 Questions 🎯 80% to pass
Start Test

Passenger Vehicle Test 3

Passenger safety and emergency procedures

📝 20 Questions 🎯 80% to pass
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Passenger Vehicle Test 4

Special situations and regulations

📝 20 Questions 🎯 80% to pass
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About School Bus Tests

School bus operation and student transportation safety

School Bus Test 1

Loading and unloading students

📝 20 Questions 🎯 80% to pass
Start Test

School Bus Test 2

Emergency exits and evacuation procedures

📝 20 Questions 🎯 80% to pass
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School Bus Test 3

Student management and safety

📝 20 Questions 🎯 80% to pass
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School Bus Test 4

Special hazards and situations

📝 20 Questions 🎯 80% to pass
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About Tanker Vehicles Tests

Liquid cargo transportation and tank vehicle operation

Tanker Vehicle Test 1

Tanker vehicle inspection and safety

📝 20 Questions 🎯 80% to pass
Start Test

Tanker Vehicle Test 2

Driving techniques for liquid cargo

📝 20 Questions 🎯 80% to pass
Start Test

Tanker Vehicle Test 3

Loading, unloading, and emergency procedures

📝 20 Questions 🎯 80% to pass
Start Test
About Doubles/Triples Tests

Double and triple trailer combinations

Doubles/Triples Test 1

Coupling and inspection procedures

📝 20 Questions 🎯 80% to pass
Start Test

Doubles/Triples Test 2

Driving techniques and safety

📝 20 Questions 🎯 80% to pass
Start Test

Doubles/Triples Test 3

Emergency procedures and troubleshooting

📝 20 Questions 🎯 80% to pass
Start Test

FAQs — Idaho CDL

Additional certifications for specialized commercial driving

Q1- Who needs a CDL in Idaho?

Drivers of:
  • Anyone driving a vehicle GVWR 26,001 lb+
  • Combinations 26,001 lb+ GCWR with a 10,001 lb.
  • Vehicles carrying 16+ passengers or
  • Hazmat..

Q2- Minimum age for CDL in Idaho?

18 intrastate, 21 interstate/hazmat/passenger.

Q3- Do I need a DOT medical card?

Yes, most CDL drivers must hold a valid Medical Examiner’s Certificate before the skills exam.

Q4- What is ELDT?

Entry‑Level Driver Training for Class A/B and H/P/S endorsements before skills/endorsement tests.

Q5- CLP holding period?

You must hold your CLP at least 14 days before the skills exam.

Q6- Where do I test?

With Idaho Transportation Department (ITD) or approved third-party testers.

Q7- Passing score?

80% minimum on each knowledge test.

Q8- Hazmat background check?

Yes — TSA background check plus hazmat knowledge test.

Q9- What to bring on test day?

Driver’s license, CLP, medical card, ELDT proof (if needed), and a compliant test vehicle for the skills exam.