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CDL Study Guide

The Commercial Driver's License is the most heavily regulated entry-level professional license in the United States. Roughly 3.5 million Americans hold an active CDL, and the federal Motor Carrier Safety Administration adds new rules almost every year. The good news: the underlying knowledge exam has not changed dramatically since the AAMVA Commercial Driver License Manual was last revised. With a focused study plan, most candidates can pass on the first attempt in two to four weeks.

Step 1 — Choose the class and endorsements you need

A Class A CDL covers any combination of vehicles where the gross combination weight is 26,001 lbs or more, and the vehicle being towed weighs more than 10,000 lbs. Class B covers single vehicles of 26,001 lbs or more and Class C covers vehicles designed to transport 16 or more passengers (including the driver) or hazardous materials in placardable amounts. Pick the class first, then layer on endorsements based on the work you intend to do: H for hazardous materials, N for tank vehicles, T for doubles/triples, P for passenger, S for school bus.

Step 2 — Get your medical card

Every CDL applicant must hold a current medical examiner's certificate from a provider on the FMCSA National Registry of Certified Medical Examiners. The exam includes vision, hearing, blood pressure, and a urinalysis screen. Schedule this early because some conditions (uncontrolled diabetes, sleep apnea, certain heart conditions) require additional documentation.

Step 3 — Read your state's CDL handbook

Every state publishes a free CDL handbook. They are nearly identical because they are derived from the AAMVA model, but the state version contains state-specific rules (weight limits, route restrictions, scheduling). Read the General Knowledge chapter and the chapter for each endorsement you need.

Step 4 — Drill with practice questions

Practice questions are how you discover what you actually know versus what you only think you know. Work through every question in the relevant CDL Prep Hub category. Aim to get above 90% before scheduling your exam:

Step 5 — Take the knowledge exams

Schedule the General Knowledge, Air Brakes, and Combination Vehicles tests together if you are going for a Class A license. Bring identification, proof of residency, your medical certificate, and the testing fee. Most applicants finish all three exams in a single visit.

Step 6 — Get your Commercial Learner's Permit (CLP)

After you pass your knowledge exams the state will issue a CLP, valid for at least 14 days. During that time you may operate a commercial vehicle only with a CDL holder of equal or greater class in the seat next to you.

Step 7 — Complete entry-level driver training

If you are applying for a CDL for the first time on or after February 7, 2022, federal regulations require Entry Level Driver Training (ELDT) at a registered training provider before you take the road test. The training has two components — theory and behind-the-wheel — and your provider will report completion to the FMCSA.

Step 8 — Pass the skills test

The skills test has three parts: a vehicle inspection, basic vehicle control (offset backing, parallel parking, alley docking), and an on-road drive. Practice each maneuver in the vehicle you will use for the test until it feels routine.

Step 9 — Receive your CDL

After passing the skills test you will be issued a full Commercial Driver's License, typically within 30 days. You are now legally qualified to drive in the class and with the endorsements you tested for.

Tips that work across every state