Free CDL Practice Test
Original questions. Real explanations for every answer. No login. No paywall.
Pick your test
What this CDL practice test is
CDL Practice Lab is a free CDL practice test for people studying for the commercial driver's license knowledge exam. Every question comes with its own written explanation, not just a right or wrong answer, and each explanation cites the actual federal regulation behind it. There's no login, no account, and no paywall. You can start practicing right away.
What's covered
We cover the three knowledge areas required of every CDL applicant (General Knowledge, Air Brakes, and Combination Vehicles) plus all five endorsements: Hazmat, Tanker, Doubles/Triples, Passenger, and School Bus. Right now that's 270 original questions across 8 sections, a number counted straight from what's actually published on the site, not a marketing figure. Start with the CDL general knowledge practice test if you're studying for your permit, or go straight to the CDL hazmat practice test if you already hold a CDL and are adding an endorsement.
Class A and Class B paths
Not sure whether you're studying for a Class A or Class B CDL? Both start with the same General Knowledge test. From there, your permit and the vehicle you'll drive determine which other sections apply to you, so practice the sections your permit actually lists rather than every section on the site. See our class A CDL practice test or class B CDL practice test page for what federal rules require for each, or our CDL study guide for the order to study every section in.
How practice works
Every question works the same way: pick an answer, then read the explanation, not just a checkmark. There's also a simulated test scored to the federal 80% passing standard set by 49 CFR 383.135, a weak-area drill that resurfaces questions you've gotten wrong, and spaced repetition that brings a question back for review before you'd naturally forget it. None of this needs an account: your progress is saved only in your browser, so it stays on your device.
Where our questions come from
We write every question and explanation ourselves, starting from the federal regulations in 49 CFR, never copied from an actual exam or any leaked test bank. State CDL manuals are used only as a topic map, to help decide which subjects to cover, never as source text we copy from. We are not affiliated with any state DMV, the FMCSA, or AAMVA. See our about page for the full methodology.
Taking your test in your state
This is easy to get wrong: your state DMV sets your test's exact question count, time limit, and the manual it's based on, not us. The one number fixed federally is the passing score, 80%, under 49 CFR 383.135. States like Illinois, New York, and Texas, for example, each publish their own manual and set their own test details; wherever you're testing, check your state DMV's own page before test day. If you searched for a dmv cdl practice test for your specific state, that's what you'll want to confirm your exact format there. Our questions are built from the federal rules that apply everywhere, not a state-specific question set, so use them to learn the material, then confirm your state's format separately.
Next steps
If you're just getting started, read how to get your CDL for the full sequence from permit to license, what a CDL costs to budget for fees and training, and the DOT medical card for the physical exam requirement. If you're stuck with an air brake restriction or pursuing the combined X endorsement, we cover those too. Got a question about how this site works? Check the FAQ.
Frequently asked questions
Is the CDL practice test free?
Yes, every practice question, explanation, and simulated test on this site is free, with no login, account, or paywall required. You can start practicing immediately and your progress is tracked right in your browser. Nothing on this site requires payment to use.
Are these the real CDL test questions?
No, these are original practice questions, not the actual test questions used by any state. No state publishes its real CDL exam, so every question here is written from the federal knowledge-test standards in 49 CFR Part 383, never copied from a real exam or another site's practice test.
How many questions are on the CDL general knowledge test?
Washington, for example, uses 50 questions for its General Knowledge test, but your own state sets the exact number of questions, not federal law. Check your own state's DMV page to confirm the exact count and time limit before test day.
What score do I need to pass the CDL written test?
The federal minimum passing score is 80 percent, set by 49 CFR 383.135. Some states require a higher score than that federal floor, so check your own state DMV for its exact requirement. Our simulated tests score against this same 80 percent standard so you know where you stand.
Which CDL knowledge tests do I need?
Every CDL applicant must pass the General Knowledge test, required under 49 CFR 383.111(a). Beyond that, you need the Air Brakes test if your vehicle has air brakes, Combination Vehicles if you're pursuing a Class A license, and a separate knowledge test for each endorsement you want, such as Hazmat or Passenger.
What is the difference between a Class A and a Class B CDL?
A Class A CDL covers a combination vehicle with a gross combination weight rating of 26,001 pounds or more where the towed unit exceeds 10,000 pounds, under 49 CFR 383.91. A Class B CDL covers a single large vehicle of 26,001 pounds or more instead. Class A additionally requires Combination Vehicles knowledge that Class B does not.
How old do I have to be to get a CDL?
You can get a commercial learner's permit at 18 under 49 CFR 383.25, but federal law separately requires drivers to be at least 21 to drive in interstate commerce or haul hazardous materials, under 49 CFR 391.11. States set their own rules for everything else, including intrastate driving below 21, so check your own state.
Do I need entry-level driver training (ELDT)?
You need ELDT if you're getting a Class A or Class B CDL, or a Passenger, School Bus, or Hazmat endorsement, for the first time, under 49 CFR 380.603. This requirement started February 7, 2022, and only applies the first time you get that class or endorsement. Training must come from a provider on FMCSA's Training Provider Registry.
Do I need a DOT medical card?
It depends on which of four self-certification categories you fall into, not simply whether you hold a CDL: only drivers who self-certify as "non-excepted interstate" are federally required to hold a medical certificate, under 49 CFR 391.45. See our medical card page for the full breakdown of all four categories.
How much does a CDL cost?
There's no single national figure, since state licensing fees and training costs both vary widely. State fees typically add up to a few hundred dollars, while training, the biggest and most variable cost, can range from a few thousand dollars to a carrier-sponsored program with little or no upfront cost. See our CDL cost breakdown for real examples.