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Free Texas CDL practice test online

Take a free Texas 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 Texas Department of Public Safety.

CDL knowledge tests are federally regulated, so the passing score in Texas 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

Texas CDL test requirements

80%
Passing score
49 CFR 383.135(a)(1)
14 days
CLP held before skills test
Texas Department of Public Safety
18
Min. age (in-state)
Texas Department of Public Safety
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 Texas Department of Public Safety is Texas’s own, and may be stricter than the federal floor. Test length, fees, and scheduling are set by Texas Department of Public Safety (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 Texas 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 Texas non-commercial knowledge test runs 30 questions and needs 21 correct, with permits issued from age 15.

Texas 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 Texas CDL practice questions

Try these Texas 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. Before changing lanes with doubles or triples you should:

    • AAccelerate into the gap immediately
    • BSignal only after you move
    • Be certain the lane is clear, signal early, and avoid sudden turning movements
    • DNever check mirrors

    Answer: Be certain the lane is clear, signal early, and avoid sudden turning movements. Sudden moves crack-the-whip the rear trailers. Take more time and space than a single trailer needs.

    Source: Commercial Driver License Manual — Doubles and triples — space management

  2. 2. Outage (expansion room) is needed in liquid tanks because:

    • AABS requires empty tanks
    • BLiquids never expand
    • Heat can expand liquid and overfill a completely full tank
    • DOutage reduces legal weight limits only

    Answer: Heat can expand liquid and overfill a completely full tank. Leave required outage so thermal expansion does not create dangerous pressure or overflow.

    Source: Commercial Driver License Manual — Tank vehicles — outage

  3. 3. Bulkheads inside a cargo tank divide it into:

    • Separate compartments for different loads or weight distribution
    • BStorage for tools
    • CInsulation layers
    • DAir chambers for braking

    Answer: Separate compartments for different loads or weight distribution. Compartments let a carrier haul more than one product and help distribute weight across the axles. Loading order then matters.

    Source: Commercial Driver License Manual — Tank vehicles — bulkheads

  4. 4. Driving alongside other vehicles for long stretches is risky because:

    • AIt improves fuel economy
    • It removes your escape path to the side
    • CIt is required on interstates
    • DMirrors become unnecessary

    Answer: It removes your escape path to the side. Keep space open on at least one side when you can so you have somewhere to go in an emergency.

    Source: Commercial Driver License Manual — Driving safely — space to the sides

  5. 5. Brake linings must be rejected during inspection if they are:

    • Loose, soaked with oil or grease, or dangerously thin
    • BA different brand than the drums
    • CPainted for corrosion protection
    • DSlightly dusty

    Answer: Loose, soaked with oil or grease, or dangerously thin. Contaminated or thin friction material cannot brake safely. Mechanical parts must also be present and unbroken.

    Source: Commercial Driver License Manual — Air brakes — walkaround inspection

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 Texas 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 Texas. Rules and manuals can change; the official agency remains authoritative.

Visit Texas Department of Public Safety
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.