The National Electrical Code (NEC), formally known as NFPA 70, is the benchmark standard for safe electrical installation in the United States. Published by the National Fire Protection Association and updated on a three-year cycle, the NEC governs virtually every wire, breaker, outlet, and panel installed in residential, commercial, and industrial settings across the country. Whether you're an apprentice electrician working toward your journeyman license, a journeyman preparing for the master electrician exam, or an electrical inspector studying for state certification, the NEC is the foundation of your licensing examination.
Electricians, electrical contractors, plan checkers, inspectors, and code consultants all rely on NFPA 70 daily. State electrical licensing boards in nearly every state — including California, Texas, Florida, New York, and Illinois — base their journeyman and master electrician exams directly on the NEC. While exact exam formats and edition requirements vary by state (more on that below), the core content tested is always drawn from the code book itself.
What makes the NEC exam unique among professional licensing tests is that most states allow the exam to be taken open-book. You're permitted to bring your physical copy of the National Electrical Code into the testing room and reference it during the exam. This changes how you should study: instead of memorizing every table and ampacity value, success depends on knowing exactly where to find the answer quickly under timed conditions. That's precisely why PDF practice tests are such a powerful prep tool — they train you to locate answers in your tabbed code book at speed.
This free NEC practice test PDF contains questions drawn from the highest-frequency articles on state electrical exams. Each question mirrors the format of actual journeyman and master electrician licensing exams: scenario-based questions that require you to apply code language, perform load calculations, or identify the correct grounding and bonding method. Download the PDF, open your NEC code book, and practice finding the answers. That workflow is the fastest way to build exam-ready speed and confidence.
State electrical licensing exams do not test the NEC uniformly. Certain articles appear on nearly every exam, year after year. Based on published exam content outlines from multiple state licensing boards, here are the six article areas that account for the majority of exam questions — and what you need to understand in each.
Article 110 sets the foundational requirements that apply throughout the code. Exam questions from this article focus on working clearances around electrical equipment (Section 110.26), which establishes minimum depth, width, and height of dedicated working space in front of panels, switchboards, and motor control centers. You'll also see questions on conductor sizing and termination temperature ratings (Section 110.14), which is a common source of calculation errors when matching conductor ampacity to equipment terminals rated at 60°C or 75°C. Understanding the "examination and use in lieu of inspection" rules and equipment listing requirements also appears regularly.
Article 210 governs branch circuit requirements and is heavily tested at both journeyman and master levels. Key topics include receptacle ratings vs. circuit ratings (Section 210.21), the small-appliance branch circuit rules for kitchens (Section 210.52), and — increasingly in recent editions — the expanded requirements for Arc-Fault Circuit Interrupter (AFCI) and Ground-Fault Circuit Interrupter (GFCI) protection. Know which locations require GFCI protection (bathrooms, garages, outdoors, kitchens, crawl spaces, unfinished basements, boathouses, and more) and which require AFCI protection (bedrooms, living rooms, and most habitable rooms in dwelling units since the 2014 edition). These rules have expanded with each new edition.
Article 220 is the calculation article and is the most math-intensive section on any electrical exam. It covers the step-by-step method for calculating branch circuit loads (Part II), feeder loads (Part III), and service entrance loads (Part IV). For dwelling units, you'll need to master the general lighting load (3 VA per square foot), mandatory small-appliance and laundry circuits, and optional calculation method vs. standard calculation method. Master electrician exams go deeper into commercial load calculations, including demand factors for specific occupancies and the heating vs. air conditioning comparison (Section 220.60). Load calculation questions are almost guaranteed to appear on your exam — practice them until they're automatic.
Article 230 covers everything from the service drop at the utility connection to the service entrance conductors, service equipment, and disconnect means inside the building. High-frequency exam topics include the number of service disconnects permitted (maximum of six disconnects in a single location under Section 230.71), service entrance conductor clearances from windows and doors (Section 230.9), and the sizing and protection rules for service entrance conductors. Understanding the difference between the service drop (utility-owned, overhead), service lateral (underground), service entrance conductors, and service equipment is essential — exam writers test these distinctions deliberately.
Article 250 is widely regarded as the hardest and most heavily tested chapter in the NEC. It covers the entire grounding and bonding system: system grounding (Part II), grounding electrode system (Part III), grounding electrode conductors (Part IV), enclosure and equipment grounding (Part V), equipment grounding conductors (Part VI), and bonding (Part VII). Exam questions focus on the difference between grounding (connecting the system to earth) and bonding (connecting metallic parts to ensure electrical continuity and safely conduct fault current), sizing the grounding electrode conductor per Table 250.66, sizing equipment grounding conductors per Table 250.122, and the main bonding jumper requirements. Spend more time on Article 250 than any other single article.
Article 300 covers the general requirements for all wiring methods — protection from physical damage, fill calculations in conduit, installation in concrete, and the rules for securing and supporting raceways. Article 310 contains the conductor ampacity tables that are the backbone of sizing calculations on every exam. You need to be comfortable finding the correct ampacity in Tables 310.12 (simplified dwelling ampacity) and 310.16 (the main 60°C/75°C/90°C table), applying correction factors for ambient temperatures above 30°C (Table 310.15(B)(1)), and applying adjustment factors for more than three current-carrying conductors in a raceway (Table 310.15(C)(1)). Conductor sizing with correction and adjustment factors is a near-certain exam topic.
The most effective way to prepare for an open-book electrical exam is to practice exactly what you'll do on exam day: read a question, form a hypothesis about which article covers it, flip to that article, and confirm the answer. This PDF is designed for that workflow.
Print the PDF or keep it open on a tablet. Work through each question with your physical NEC code book beside you. When you find the answer, write the article and section number next to the question. After completing a full practice set, review your wrong answers and add index tabs for any article you struggled to locate. Over time, you'll build a mental map of the code book that dramatically reduces your lookup time during the real exam.
Open-book vs. closed-book exams by state: The majority of US states administer open-book electrical licensing exams, meaning your NEC code book is your primary tool during the test. However, some states — including Florida (which uses an open-book format with approved references) and others — have specific rules about which materials you can bring. A small number of states use closed-book exams or restrict references to specific appendices. Always confirm your state's current exam rules with your state electrical licensing board before your exam date. Your state board's website will list the approved exam references and edition of the NEC currently in use.
For a complete overview of NEC exam topics, state licensing requirements, and additional free practice tests, visit our NEC National Electrical Code Certification page. It includes exam format details, additional practice questions by article, and links to official state licensing board resources.