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Free Maryland CDL practice test online

Take a free Maryland 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 Maryland Motor Vehicle Administration.

CDL knowledge tests are federally regulated, so the passing score in Maryland is the same as everywhere else: 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

Practice coverage
Complete a run to establish your baseline.
600questions
23topics
80%federal pass mark

49 CFR 383.135(a)(1) sets the CDL knowledge-test passing score at 80%. Reaching it here is not a prediction of your official result.

Requirements before you test

Maryland CDL test requirements

80%
Passing score
49 CFR 383.135(a)(1)
14 days
CLP held before skills test
Maryland Motor Vehicle Administration
18
Min. age (in-state)
Maryland Motor Vehicle Administration
21
Min. age (interstate)
49 CFR 391.11(b)(1)

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 Maryland Motor Vehicle Administration is Maryland’s own, and may be stricter than the federal floor. Test length, fees, and scheduling are set by Maryland Motor Vehicle Administration (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 Registry

You need a Maryland 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 Maryland non-commercial knowledge test runs 25 questions and needs 22 correct, with permits issued from age 15 years, 9 months.

Maryland permit practice test
Quick practice
10 balanced questions with feedback after every answer.
Topic review
Focus on one knowledge area before returning to mixed practice.
Exam-style run
Answer the full starter bank before seeing your results.

Sample questions

5 Maryland CDL practice questions

Try these Maryland 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. 1. A “wig-wag” low-air warning is a device that:

    • Drops into the driver’s view and will not stay up until pressure is restored
    • BReplaces the safety valve
    • CLocks the fifth wheel
    • DIncreases compressor speed

    Answer: Drops into the driver’s view and will not stay up until pressure is restored. Some vehicles use a drop-arm wig-wag in addition to or instead of lamps/buzzers for low-air warning.

    Source: Commercial Driver License Manual — Air brakes — low pressure warning devices

  2. 2. A posted speed for a curve should be treated by a commercial driver as:

    • AApplicable only in the rain
    • BThe safe speed for any loaded vehicle
    • CA minimum to maintain
    • A limit set for cars, so slow further

    Answer: A limit set for cars, so slow further. Posted curve speeds assume passenger cars. A high, heavy load can roll over at a speed a car handles comfortably.

    Source: Commercial Driver License Manual — Driving safely — curves

  3. 3. If a school bus is stalled on or adjacent to a railroad-highway crossing, the driver must:

    • AKeep students on the bus and wait for the train
    • Evacuate the bus
    • CMove students onto the tracks away from traffic
    • DOnly call dispatch and remain seated

    Answer: Evacuate the bus. A stalled bus on the crossing is a mandatory evacuation situation.

    Source: Commercial Driver License Manual — School buses — mandatory evacuations

  4. 4. While the bus is moving, the aisle should be:

    • AUsed for cargo only
    • BBlocked by the driver’s personal bags
    • CFilled with standing passengers when seats are full
    • Kept clear so passengers can reach exits

    Answer: Kept clear so passengers can reach exits. A clear aisle is required for emergency evacuation and for safe movement of passengers when needed.

    Source: Commercial Driver License Manual — Passenger vehicles — prohibited practices

  5. 5. The standee line on a bus marks:

    • AThe emergency exit only
    • BThe fare box queue
    • CWhere baggage may be stacked
    • Where standing riders must stay behind (no standing forward of the rear of the driver’s seat)

    Answer: Where standing riders must stay behind (no standing forward of the rear of the driver’s seat). Buses that allow standing use a floor line or equivalent so riders do not block the driver.

    Source: Commercial Driver License Manual — Passenger vehicles — standee line

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 Maryland just like everywhere else — the endorsement guide explains how the codes fit together.

General knowledge

The foundation for commercial driving: inspections, space, speed, communication, hazards, and safe operation.

  • Pre-trip inspection
  • Space and speed management
  • Railroad crossings
  • Emergency procedures
Practice general knowledge
Air brakes

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
Practice air brakes
Combination vehicles

Prepare for safe coupling, inspection, turning, backing, and handling of tractor-trailer combinations.

  • Fifth-wheel inspection
  • Coupling and uncoupling
  • Off-tracking
  • Trailer skid prevention
Practice combination vehicles
Hazardous materialsEndorsement H

Study hazard communication, shipping papers, placards, loading rules, parking, and emergency response responsibilities.

  • Hazard classes
  • Placards and labels
  • Shipping papers
  • Loading and segregation
Practice hazardous materials
Tank vehiclesEndorsement N

Learn how liquid surge, outage, bulkheads, and high centers of gravity change vehicle handling.

  • Liquid surge
  • Outage requirements
  • Smooth braking
  • Rollover prevention
Practice tank vehicles
Doubles & triplesEndorsement T

Practice converter-dolly inspection, coupling order, rearward amplification, and stability principles.

  • Coupling sequence
  • Converter dollies
  • Rearward amplification
  • Space management
Practice doubles & triples
Passenger vehiclesEndorsement P

Prepare to inspect, load, and operate buses while keeping passengers, aisles, and exits safe.

  • Vehicle inspection
  • Passenger loading
  • Emergency exits
  • Prohibited practices
Practice passenger vehicles
School busEndorsement S

Review student loading, danger zones, mirrors, emergency procedures, and special railroad-crossing duties.

  • Danger zones
  • Student loading
  • Mirror use
  • Railroad crossings
Practice school bus
Official source hub
Verify current rules before your test.

QuizLane’s starter material points learners back to the agency responsible for licensing in Maryland. Rules and manuals can change; the official agency remains authoritative.

Visit Maryland Motor Vehicle Administration
Our accuracy promise
Original wording—not scraped competitor questions
A source section attached to every reviewed item
A correction path when something looks wrong
Read our methodology

Common questions

What this practice can—and cannot—tell you.