CDL General Knowledge Test: How Many Questions?
The CDL general knowledge test runs 50 multiple-choice questions in most states, with 80 percent (40 correct) needed to pass. Illinois is a documented exception at just 30 questions, still at an 80 percent passing bar. The count and the topics tested come from each state’s own CDL manual, built around the same federal knowledge list every state has to cover, but the exact number of questions on the page in front of you depends on which state you’re sitting in.
This isn’t the same question as “how many questions across every CDL test,” endorsements included. This page looks specifically at the general knowledge section, the one every applicant takes regardless of vehicle class, and at what’s actually packed inside that question count: how it’s split across topics, how states that use randomized banks differ from states with fixed question sets, and what a failed attempt costs you in wait time.
CDL is the name of a real license category issued by state driver-licensing agencies. This page is not affiliated with FMCSA or any state DMV.
How many questions are on the general knowledge test?
50 is the number in most states. Texas and California both run the general knowledge test at 50 questions with 40 correct required to pass (Texas DPS, Commercial Driver License; California DMV Commercial Driver Handbook), and Georgia and New York use the same 50-question, 40-correct format (Georgia DDS, Commercial Driver’s Study Guide; NY DMV, New York State Commercial Driver’s Manual). Illinois breaks that pattern: its computerized General (Core) Knowledge test is set at 30 standardized, random multiple-choice questions, still requiring 80 percent correct, which works out to 24 of 30 (Illinois Secretary of State, Commercial Driver’s License (CDL) and Commercial Learner’s Permit (CLP)). Federal rule 49 CFR 383 sets the topics every state must test and the 80 percent passing standard, but it never fixes a question count, which is exactly how Illinois ends up with a shorter test than its neighbors.
What topics fill those 50 (or 30) questions?
The general knowledge section pulls from a handful of recurring topic areas regardless of state: safe driving practices and hazard perception, vehicle inspection basics, basic vehicle control, cargo handling fundamentals, hours-of-service awareness, and accident procedures. States don’t typically publish an exact question-per-topic breakdown, since the pool the test draws from (Texas puts its general knowledge pool at roughly 250 possible questions) is deliberately large enough that memorizing a fixed sequence doesn’t work (Texas DPS, Texas CMV Driver’s Handbook). Illinois’s system goes further: because its 30-question set is pulled at random from a larger bank each time, no two applicants necessarily see the same 30 questions on the same day.
Fixed pool vs. random draw: why practice sites disagree on counts
Some states test from a fixed, published pool of possible questions; others draw at random for every attempt. Both approaches land on the same passing standard, 80 percent, but they change how you should study. A fixed-pool state rewards working through every question in the manual’s practice sections. A random-draw state like Illinois rewards understanding the underlying concept, since the specific wording you’ll face isn’t predictable in advance. Third-party practice sites often quote outdated question counts because they’re built around an older manual edition or a state that has since changed its format, so the count you see on a general “CDL practice test” site isn’t a substitute for checking your own state’s current manual.
Question count and retest cost by scenario
| Scenario | Typical question count | Passing score | What a fail costs you |
|---|---|---|---|
| Most states, first attempt | 50 | 40 correct (80%) | Same-day or short-wait retest in many states |
| Illinois, first attempt | 30 | 24 correct (80%) | Retest allowed, but a 3rd fail triggers a 30-day wait |
| Illinois, after 6 total fails on the same test | 30 | 24 correct (80%) | 90-day wait before the next attempt |
| Illinois, after 9 total fails on the same test | 30 | 24 correct (80%) | 1-year wait from the date of the last fail |
Source: Illinois Secretary of State, Commercial Driver’s License (CDL) and Commercial Learner’s Permit (CLP). Illinois’s tiered wait period is a documented consequence of the shorter, randomized question format, since repeated fails there escalate faster than a simple same-day retest.
Run a timed, randomized set in the CDL Practice Hub CDL practice quiz before you commit to a test date. Knowing the topics on paper is different from answering 30 or 50 of them correctly against a clock, especially if your state draws questions at random.
Does a shorter test mean it’s easier?
Not necessarily. A 30-question test at 80 percent gives you six wrong answers before you fail; a 50-question test at the same percentage gives you ten. The margin for error scales with the question count, so Illinois’s shorter test actually leaves less room to miss questions than the 50-question format most other states use, even though the topics covered are functionally the same.
If a study packet built around the actual topic list, not just a raw practice question dump, sounds useful, that’s what the CDL Practice Hub CDL permit study guide covers.
FAQ
Is 50 questions the federal standard for the CDL general knowledge test? No. Federal law sets the topics and the 80 percent passing standard, but not a fixed question count. 50 is simply what most states have chosen; Illinois uses 30.
Why do practice test websites list different question counts for the same state? Many are built around an older manual edition or generalize across states without checking each one’s current format. Always confirm the count against your own state’s current CDL manual.
Does missing more questions on a 50-question test hurt more than on a 30-question test? No, the percentage threshold is what matters, not the raw number missed. But a shorter test gives you fewer wrong answers before you cross the failing line, which changes how much margin you’re working with.
How many times can I retake the general knowledge test if I fail? It varies by state. Illinois allows retakes but escalates the wait period after every third failure on the same exam, from 30 days up to a full year. Check your own state’s retest policy before assuming unlimited same-day attempts.
Do endorsement tests use the same question count as the general knowledge test? No. Each endorsement (hazmat, passenger, tank, and the rest) runs its own separate test with its own question count, set independently by each state, on top of the general knowledge test.