CDL Commercial Drivers License General Knowledge
Find out if you’ll pass.
25 questions across 4 topics. You’ll know exactly where your gaps are — and where your study time should go. No signup required.
Start Readiness Check →What you’ll get
✓Pass or fail prediction scored against the 80% passing line
✓Topic-by-topic breakdown — exactly where you’re strong and where you’re not
✓Every question you missed — with explanations
✓Here’s exactly where your study time should go
How Prepdex works
About the CDL Commercial Drivers License General Knowledge
The CDL Commercial Drivers License General Knowledge has 50 multiple-choice questions and a 60-minute time limit. You need a score of approximately 80% to pass.
The exam covers 4 knowledge domains:
General Knowledge
40%
Air Brakes
20%
Combination Vehicles
20%
Pre-Trip Inspection
20%