Free Idaho CDL practice test online
Take a free Idaho CDL practice exam online with clear explanations—no sign-up. Coverage includes general knowledge, vehicle systems, combination vehicles, cargo, and endorsements. Then verify current requirements with Idaho Division of Motor Vehicles.
Idaho Division of Motor Vehicles gives the general knowledge test as 50 questions, and federal law sets the bar at 80% correct on every knowledge test. You must also hold a commercial learner’s permit for 14 days before the skills test.
New to the knowledge test? CDL endorsements explained · One-week study plan
Requirements before you test
Idaho CDL test requirements
Commercial licensing is largely federal. Any figure above credited to a 49 CFR section applies in every state — see 49 CFR 383.135(a)(1) and 49 CFR 383.25(e). A figure credited to Idaho Division of Motor Vehicles is Idaho’s own, and may be stricter than the federal floor. Test length, fees, and scheduling are set by Idaho Division of Motor Vehicles (official source).
Entry-Level Driver Training comes first
Since February 7, 2022, a new Class A or Class B CDL, a class upgrade, or a first passenger, school bus, or hazardous materials endorsement requires training from a provider on the FMCSA Training Provider Registry (49 CFR 380.600). Practice questions are study material and do not satisfy that requirement.
FMCSA Training Provider RegistryYou need a Idaho licence first
A commercial learner’s permit only counts if you already hold an ordinary licence from the same state (49 CFR 383.25(a)(2)). The Idaho non-commercial knowledge test runs 40 questions and needs 34 correct, with permits issued from age 14 years, 6 months.
Idaho permit practice testWhat you will practice
Build coverage topic by topic.
Each question carries a topic, difficulty, explanation, and source section so your review has context.
Sample questions
5 Idaho CDL practice questions
Try these Idaho sample questions now — each shows the correct answer with a plain-language explanation and a source section. The full 600-question bank is in the practice run.
1. If you miss a student’s unloading stop, you should:
- AOpen the rear emergency door
- BBack up to the stop
- Not back up; follow local procedures for a safe alternative
- DDischarge the student at the next driveway
Answer: Not back up; follow local procedures for a safe alternative. Backing a school bus is hazardous. Local policy covers how to correct a missed stop without reversing into the danger zone.
Source: Commercial Driver License Manual — School buses — unloading
2. During inspection of a doubles combination, the pintle hook must be:
- ARemoved while loading
- BResting on the safety chains
- CGreased and left open
- Latched closed with its lock engaged
Answer: Latched closed with its lock engaged. An unlatched pintle hook can release the towed trailer. Confirm the latch and any secondary lock are seated.
Source: Commercial Driver License Manual — Doubles and triples — converter dollies
3. No matter how short a piece of cargo is, it should have at least:
- AFour tiedowns
- BNo tiedowns if under 50 pounds
- COne tiedown
- Two tiedowns
Answer: Two tiedowns. Also use at least one tiedown for every 10 feet of cargo length as a general rule.
Source: Commercial Driver License Manual — Securing cargo — tiedowns
4. When backing under a trailer to couple, you should approach:
- AAt a sharp angle for leverage
- In a straight line so the kingpin enters the fifth-wheel jaws squarely
- CWith the landing gear fully raised first
- DWith glad hands already connected
Answer: In a straight line so the kingpin enters the fifth-wheel jaws squarely. A straight approach helps the kingpin hit the throat of the fifth wheel correctly for a secure lock.
Source: Commercial Driver License Manual — Combination vehicles — coupling
5. You may drive a vehicle carrying hazardous materials without an H endorsement if:
- AThe tanks are empty
- BAny amount is aboard
- The load does not require placards
- DYou stay on secondary roads
Answer: The load does not require placards. Not every hazmat shipment requires placards. If placards are required, the endorsement is required.
Source: Commercial Driver License Manual — Hazardous materials — placarding
CDL knowledge areas
Classes and endorsements, organized.
Each area below scopes the reviewed question bank to one knowledge test. The material is federal, so it applies in Idaho just like everywhere else — the endorsement guide explains how the codes fit together.
The foundation for commercial driving: inspections, space, speed, communication, hazards, and safe operation.
- Pre-trip inspection
- Space and speed management
- Railroad crossings
- Emergency procedures
Understand air-brake components, inspections, warning devices, stopping distance, and controlled braking.
- Dual air systems
- Low-air warnings
- Brake lag and fade
- Applied-leak and static checks
Prepare for safe coupling, inspection, turning, backing, and handling of tractor-trailer combinations.
- Fifth-wheel inspection
- Coupling and uncoupling
- Off-tracking
- Trailer skid prevention
Study hazard communication, shipping papers, placards, loading rules, parking, and emergency response responsibilities.
- Hazard classes
- Placards and labels
- Shipping papers
- Loading and segregation
Learn how liquid surge, outage, bulkheads, and high centers of gravity change vehicle handling.
- Liquid surge
- Outage requirements
- Smooth braking
- Rollover prevention
Practice converter-dolly inspection, coupling order, rearward amplification, and stability principles.
- Coupling sequence
- Converter dollies
- Rearward amplification
- Space management
Prepare to inspect, load, and operate buses while keeping passengers, aisles, and exits safe.
- Vehicle inspection
- Passenger loading
- Emergency exits
- Prohibited practices
Review student loading, danger zones, mirrors, emergency procedures, and special railroad-crossing duties.
- Danger zones
- Student loading
- Mirror use
- Railroad crossings
More west practice
Nearby CDL practice tests
Jump to another west state hub, or browse every jurisdiction.
Common questions
What this practice can—and cannot—tell you.