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Free practice questions, study guides, and optics calculators for ABO, NCLE, and COA candidates. Corrections welcome.

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optical.education is an independent educational resource. It is not affiliated with, endorsed by, or sponsored by the American Board of Opticianry and National Contact Lens Examiners (ABO-NCLE), the International Joint Commission on Allied Health Personnel in Ophthalmology (IJCAHPO), or any state licensing board. Content is for study support only and is not medical, legal, or professional advice. Always confirm current requirements with the official source.

Exam and credential names (such as ABO, NCLE, NOCE, CLRE, ABOC, and NCLEC) are used only to describe the exams and credentials offered by ABO-NCLE. COA®, COT®, and COMT® are registered marks of IJCAHPO. All marks belong to their respective owners.

ABO-NCLE alone decides ABO and NCLE exam rules and fees, and IJCAHPO is the only authority for COA® exam rules and fees. We check those facts against each body’s own pages and handbooks and note where they disagree.

© 2026 optical.education · Content last reviewed Oct 22, 2026

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