Have you ever looked at your identity document and wondered what is this string of numbers and personal information at the bottom? It’s a machine-readable zone or in short MRZ and its purpose is to facilitate automated reading of basic personal details from the document during the verification process. An MRZ consists of two or three lines of characters, checksum numbers and separators. It can be placed on the front side of the document or in the back.
After the Second World War the United Nations created the International Civil Aviation Organization. One of its responsibilities was to establish a uniform template for travel documents. In the late 60’s they started to work on Machine-Readable Travel Documents. They used Optical Character Recognition (OCR) which gives a machine the ability to process a script that a human can also read. In 1980’s countries began to issue machine-readable travel documents, which had the machine-readable zone. It contained basic information such as the document number, expiration date, name of the holder, gender, date of birth, and citizenship. New improvements are still added like a biometric chip, containing the holder’s information. Nowadays MRZ is used not only in passports but also in identity documents and even in driving licences. The MRZ provides an additional layer of security for the personal data, as it contains check sums and syntactic rules which helps prevent forgery attempts.
Any document that has been issued according to ICAO standards comprises two parts – the Visual Inspection Zone (VIZ), and the Machine-Readable Zone (MRZ). The Visual Inspection Zone comprises the mandatory and optional data elements designed for visual inspection, like: the holder’s facial image, personal data and data concerning issue and validity. Machine Readable Zone contains some information from the VIZ. The MRZ contains digits, letters without special signs and filler characters. The font used for these characters is defined by the ICAO and has a number of distinct attributes.
There are several types of ICAO standard machine-readable zones. They differ in the number of lines and characters in each line. Most of the identity documents have 3 lines of MRZ and 30 characters each. Passports have 2 lines with 44 characters each. The MRZ code of a passport always has two lines of characters, which correspond to the data from the VIZ. In identity documents the information in MRZ are the same as in the passport but in a different order. The information that needs to be in the machine-readable zone are:
With ID cards, the first character in the MRZ indicates the type of document – I for ID card, P for passport, V for visa. Next is the country code and the three characters that indicate the country that issued the document. The country code is in accordance with International Organization for Standardization standards. The next characters are the document number followed by the check digit to the document number.
Second line of the ID card MRZ opens with the holder’s birthdate in the YYMMDD format, after which there is a check digit. It is calculated by an algorithm based on the date of birth. Next there is the gender of the document holder: male (M), female (F), or a placeholder < in case the person has not decided on their gender or refused to provide it. The next 6 digits indicate the validity period of the ID card in the same format as the birth date, followed by the check digit. Following three characters indicate the citizenship of the document holder. Last digit is the check digit to the entire second line.
Third line in the ID cards contains the last name separated from the first by two placeholders. Lastly there are given names of the document holder. If a document owner has more than one name they are separated by one placeholder.
During the verification process the identity document needs to be photographed, the higher resolution the better. Once the MRZ is captured on the photograph it is scanned and the text is recognized using the optical character recognition (OCR) system. The checksums are also scanned and compared with the original checksums for data verification. The data can also be compared with the visual zone to see if they are a match.
The machine-readable zone prevents alteration in the document. All of the information in the MRZ is in a standardized format, so it speeds up the verification process and allows specialists to read the data in all of the countries. It can also allow access to a chip that is placed in the biometric passports. From that chip more information about the holder can be extracted.
The machine-readable zone is an important part of the identity verification process. It allows for a quick identification and can be used not only in airports but also in businesses and organizations. With so many fraud attempts it is important to check identity documents with much care. Especially when so many businesses have moved online. Documents have multiple security features not only in the substrate that they are made from but also in its content. MRZ codes are a very important part of those features. Choosing the right identity verification provider can improve client onboarding. Fully-Verified offers optical recognition systems that scan the passport and other identity documents. We can support verification from over 230 countries with over 7700 document types.