Magnetic ink character recognition

Cheque sample for a fictional bank in Canada using par-crossing MICR encoding for cashing in the United States

Magnetic Ink Character Recognition, or MICR, is a character recognition technology used primarily by the banking industry to facilitate the processing of cheque and makes up the routing number and account number at the bottom of a check. The technology allows computers to read information (such as account numbers) off printed documents. Unlike barcodes or similar technologies, however, MICR codes can be easily read by humans.

MICR characters are printed in special typefaces with a magnetic ink or toner, usually containing iron oxide. As a machine decodes the MICR text, it first magnetizes the characters in the plane of the paper. Then the characters are passed over a MICR read head, a device similar to the playback head of a tape recorder. As each character passes over the head it produces a unique waveform that can be easily identified by the system.

The use of magnetic printing allows the characters to be read reliably even if they have been overprinted or obscured by other marks, such as cancellation stamps and signature. The error rate for the magnetic scanning of a typical check is smaller than with optical character recognition systems. For well printed MICR documents, the "can't read" rate is usually less than 1% while the substitution rate (misread rate) is in the order of 1 per 100,000 characters.

MICR is standardized by ISO 1004:1995.

Fonts

The major MICR fonts used around the world are E-13B and CMC-7. In the 1960s, the MICR fonts became a symbol of modernity or futurism, leading to the creation of lookalike "computer" typefaces that imitated the appearance of the MICR fonts, which unlike real MICR fonts, had a full character repertoire.

The 14 characters of the E-13B font. The control characters bracketing each numeral block are (from left to right) transit, on-us, amount, and dash.

Almost all US, Canadian and UK cheques use the E-13B font. (The "13" in the font's name refers to the 0.013 inch grid used to design it.) Besides decimal digits it also contains the following symbols: ⑆ (transit: used to delimit a bank branch routing transit number), ⑇ (amount: used to delimit a transaction amount), ⑈ (on-us: used to delimit a customer account number), and ⑉ (dash: used to delimit parts of numbers, e.g., routing numbers or account numbers).

An example of the CMC-7 MICR font. Shown are the 15 characters of the CMC-7 font. The control characters after the numerals are (from left to right) internal, terminator, amount, routing, and an unused character.

Some countries, including France, use the CMC-7 font developed by Bull.

Unicode

MICR characters were added to the Unicode Standard in June, 1993 with the release of version 1.1.

The Unicode block that includes MICR characters is called Optical Character Recognition and covers U+2440–U+245F:

Optical Character Recognition Unicode.org chart (PDF)

0

1

2

3

4

5

6

7

8

9

A

B

C

D

E

F

U+244x

⑀

⑁

⑂

⑃

⑄

⑅

⑆

⑇

⑈

⑉

⑊

U+245x

Notes 1.^ As of Unicode version 6.1

See also

• OCR-A font
• OCR-B
• Routing transit number
• Westminster (typeface)

External links

• What is MICR
• MICR E-13B Character set
• History of MICR and the Check
• GNU General Public Licensed MICR font
• X9 Standards overview document of all MICR-related standards and how they are organized
• The early days of Desktop Laser MICR Check Printing
• History of MICR