MRZ

MRZ stands for Machine Readable Zone, the machine-readable portion of many travel documents such as passports and national identity cards. It is designed to be read by optical character recognition (OCR) systems at border checkpoints and by automated data capture processes. MRZ data is standardized by the International Civil Aviation Organization (ICAO) under Document 9303 and is used worldwide.

MRZ appears as two or three lines of characters printed in OCR-B font at the bottom of the passport or on visible areas of ID documents. The most common formats are TD3 for passports (two lines of 44 characters) and TD1 for many identity cards (three lines of 30 characters). Each format uses a restricted character set and a padding character '<' to fill unused positions.

The MRZ encodes core personal and document data: document type and issuing country, the holder's name (surname and given names) or names separated by '<', the document number, nationality, date of birth, sex, and the document expiration date. Several check digits are calculated with a Modulo-10 algorithm to verify the integrity of the document number, birth date, expiration date, and a composite field.

During border checks, MRZ is scanned or photographed, then decoded to populate traveler records and facilitate automatic validation against watchlists or databases. Because MRZ carries sensitive personal data, its security and correct handling are important, and errors in reading can trigger manual checks.