What is MRZ?
MRZ stands for Machine Readable Zone. It is the block of
text at the bottom of passports, ID cards, and visas that
scanners read in seconds.
ICAO 9303 defines the MRZ so every country reads the same fields
in the same positions. That is why the MRZ looks similar no
matter where a document is issued.
The MRZ is printed in OCR-B, a special font made for
machine reading. Each character takes the same amount of space
(like a typewriter), so scanners can split the line into equal
boxes and read it reliably.
That fixed spacing is the reason the MRZ uses OCR-B even when
the rest of the document uses a different font.
OCR-B (spec font)
K123456784NZL9907054F3101023ABCD1234<<<<<<44
What data is encoded
Common fields include document type, issuing country, document
number, name, nationality, date of birth, sex, expiry date, and
optional data.
Dates are encoded as YYMMDD (for example, 12 July
1942 becomes 420712).
MRZ layouts by document type