CDL Scoring Guide
How scores are calculated, what they mean, and how to reach your goal score.
Scoring Overview
Most CDL knowledge tests require 80% to pass. The General Knowledge test is 50 questions; endorsement tests have fewer questions but the same 80% threshold. Written tests are followed by skills tests (pre-trip, backing, road test).
Score Scale
| Section | Duration | Max Score |
|---|---|---|
| CDL General Knowledge | 90 min | 100 |
Section Breakdown
general knowledge
General Knowledge — required for all CDL applicants.
Vehicle inspectionBasic controlsShifting and backingSpace managementNight/adverse drivingHazardous conditionsAccidentsPre-trip inspection
endorsements
Endorsements — add special vehicle authority to your CDL.
HazMat (H) — hazardous materialsTanker (N) — liquid cargoCombination (T) — doubles/triplesPassenger (P) — busSchool Bus (S)
Key Facts
- Knowledge tests
- General Knowledge + endorsements
- Questions
- 50 (General Knowledge)
- Passing score
- 80% (40 of 50)
- Cost
- ~$50–$100 (varies by state)
- CDL classes
- Class A (combo), B (heavy), C (special)
- Medical
- DOT medical exam required
Study Tips
- 1.Your state's CDL manual is the only source you need — read it cover to cover.
- 2.Hours of Service rules are complex — make a cheat sheet with the key numbers (11h driving, 14h window, 10h reset, 70h in 8 days).
- 3.Air brakes endorsement: know the three brake tests (static, governor, low air warning).
- 4.For HazMat: memorize the 9 hazard classes and their placard requirements.
- 5.Use free CDL practice tests on DMV.org or cdlpracticetest.com — they mirror real exam format.
- 6.After passing knowledge tests, get hands-on driving hours with a CDL school or mentor before your skills test.