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WireNerd is here to help you learn and prepare. It is not professional advice, and it is not a substitute for the code, formal training, or a licensed electrician.

Last updated: June 7, 2026

Educational use only

All content on WireNerd — lessons, guides, the wiring sandbox, the components reference, and exam-prep material — is provided for general educational purposes. It is not engineering, design, legal, or professional advice, and it should not be relied on as the sole basis for any electrical work or decision.

Not a school or licensing authority

WireNerd is an independent resource. It is not an accredited school, training academy, or licensing authority, and it is not affiliated with NFPA, the National Electrical Code, or any state or government agency. Using this site does not grant any license, certification, or official credential.

Certificates of completion

Any certificate you earn on WireNerd is a certificate of completion only — a record that you worked through the material. It is not issued by an accredited school, and it is not a license, professional certification, or any official credential. It carries no formal or regulatory standing on its own.

No guarantee of results

Studying with WireNerd does not guarantee you will pass any exam or obtain any license. Exam content, formats, and requirements vary by state and change over time — always confirm current requirements with your own licensing board.

Electrical safety. Electrical work is dangerous and can cause serious injury, fire, or death. Do not perform electrical work based solely on anything you read or build here. Always verify against the current adopted edition of the code and your local authority having jurisdiction (AHJ), follow proper safety practices, and consult a licensed professional. The interactive sandbox is a simplified simulation for learning — real circuits behave differently.

Code references & accuracy

WireNerd's practice questions and explanations are original. We do not reproduce the text of NFPA 70 (the NEC); code references are pointers only and you should verify every one against your own current copy of the code. We work to keep content accurate but make no warranty that it is complete, current, or error-free.

Limitation of liability

To the fullest extent permitted by law, WireNerd and Bryan Barrios are not liable for any loss, injury, or damage arising from your use of this site or reliance on its content. You use the site and the sandbox at your own risk.