Free CDL practice test
General-knowledge questions drawn from the standard CDL manual, with a plain-English explanation after every answer. No account, no paywall — just practice until it sticks.
To recover from a drive-wheel acceleration skid, you should:
How the CDL knowledge test works
To earn a commercial driver's license you first pass written knowledge tests at your state DMV, then a skills test in the class of vehicle you intend to drive. Every driver takes the general knowledge test. Depending on the vehicle and cargo, you may also need endorsement tests for air brakes, combination vehicles, tankers, or hazardous materials.
The passing bar is typically around 80%. The questions here reshuffle on every attempt, so retake the test until you are scoring above that consistently. When you're planning the rest of the process, see what a CDL costs and the pre-trip inspection checklist for the skills test.
Practice by state
Frequently asked
- How many questions are on the real CDL general knowledge test?
- Most states ask 50 general-knowledge questions and require about 80% correct to pass. The exact number and passing score vary by state.
- Is this the official CDL test?
- No. This is free study material built from the standard CDL manual topics. Use it to prepare, then take the official test at your state DMV.
- What endorsements do I need to study separately?
- Beyond general knowledge, you may need air brakes, combination vehicles, hazardous materials (HazMat), tanker, doubles/triples, or passenger endorsements depending on what you will drive.