# CDL Answers

> CDL Answers is the #1 CDL practice test app, helping aspiring commercial drivers pass their CDL written exams across all 50 US states.

## About

CDL Answers provides 1,200+ practice questions for all 9 CDL test types (General Knowledge, Air Brakes, Combination Vehicles, HAZMAT, Passenger, School Bus, Tanker, Doubles/Triples, and Pre-Trip Inspection). Questions closely mirror real CDL exams and include detailed explanations. Available on web, iOS, and Android.

## Content Structure

The site is organized into three main sections:

### Practice Tests (/cdl-practice-tests)
- 50 state-specific hubs: /cdl-practice-tests/{state}
- 9 test pages (one per federally-standardized test type): /cdl-practice-tests/tests/{test-type}
- Individual question pages with answers and explanations: /cdl-practice-tests/{state}/{test-type}/{question-slug}

State hubs include state-specific CDL requirements: minimum age, DMV agency details, renewal frequency, ELDT requirements, and economic context.

Test types available:
- general-knowledge: Core CDL written test (all drivers)
- air-brakes: Air brake system knowledge
- combination-vehicles: Class A combination vehicle operation
- hazmat: Hazardous materials endorsement
- passenger: Passenger vehicle endorsement (16+ passengers)
- school-bus: School bus endorsement
- tanker: Tanker vehicle endorsement
- doubles-triples: Doubles/triples trailer endorsement
- pre-trip-inspection: Vehicle inspection procedure

### Study Guides (/guides)
- What Is a CDL?: /guides/what-is-a-cdl
- How to Get a CDL: /guides/how-to-get-a-cdl
- CDL Permit / CLP Guide: /guides/cdl-permit
- CDL Classes Explained: /guides/cdl-classes
- CDL Endorsements: /guides/cdl-endorsements
- CDL Test Questions: /guides/cdl-test-questions
- CDL Passing Score: /guides/cdl-passing-score
- How to Pass the CDL Test: /guides/how-to-pass-cdl-test
- CDL Test Cost: /guides/cdl-test-cost

### Endorsement Guides (deep per-endorsement informational pages)
- HAZMAT Endorsement: /guides/hazmat — $86.50 TSA fee, fingerprinting, disqualifying offenses (49 CFR 1572), 30-question test
- Tanker Endorsement: /guides/tanker — liquid surge handling, smooth-bore vs baffled tanks, 1,000-gallon threshold (49 CFR 383.5), 20-question test
- Passenger Endorsement: /guides/passenger — 16-passenger threshold (49 CFR 383.5), evacuation responsibility, ADA accessibility (49 CFR Part 37), 20-question test
- School Bus Endorsement: /guides/school-bus — railroad-crossing rule (49 CFR 392.10), danger zones, evacuation drills, federal-floor vs state-additions framing, 20-question test (requires P first)
- Doubles/Triples Endorsement: /guides/doubles-triples — coupling sequence, off-tracking + crack-the-whip, STAA highways (23 CFR 658), the 1991 ISTEA LCV freeze, 20-question test on a Class A CDL
- Air Brakes (L restriction removal — NOT an endorsement): /guides/air-brakes — restriction removal under 49 CFR 383.95, the in-cab air brake test, federal pressure thresholds (low-air warning at 55 psi per 49 CFR 393.51), spring brake activation 20-45 psi (FMVSS 121)

### Pricing (/pricing)
Freemium model: free practice questions available, paid subscription for full access.

## Key Facts
- 1,200+ practice questions across 9 test types
- Coverage for all 50 US states with state-specific content
- 4.8/5 App Store rating (655 ratings)
- Questions sourced from real CDL exam prep materials
- Updated regularly to reflect current exam content
- Built and maintained by CDL holders

## Contact
- Website: https://cdlanswers.com
- App Store: https://apps.apple.com/app/cdl-answers/id6737094961