ISO/IEC 18004:2006

Information technology - Automatic identification and data capture techniques - QR Code 2005 bar code symbology specification

ISO/IEC 18004:2006 defines the requirements for the symbology known as QR Code 2005. It specifies the QR Code 2005 symbology characteristics, data character encoding methods, symbol formats, dimensional characteristics, error correction rules, reference decoding algorithm, production quality requirements, and user-selectable application parameters, and lists in an informative annex the features of QR Code Model 1 symbols which differ from QR Code 2005.

Technologies de l'information — Techniques automatiques d'identification et de capture des données — Spécification de symbologie de code à barres, code QR 2005

General Information

• Status: Withdrawn
• Publication Date: 30-Aug-2006
• Withdrawal Date: 30-Aug-2006
• ICS: 01.080.50 - Graphical symbols for use on information technology and telecommunications technical drawings and in relevant technical product documentation
• ICS: 35.040 - Information coding
• ICS: 35.040.50 - Automatic identification and data capture techniques
• Technical Committee: ISO/IEC JTC 1/SC 31 - Automatic identification and data capture techniques
• Drafting Committee: ISO/IEC JTC 1/SC 31/WG 1 - Data carrier
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 16-Feb-2015
• Completion Date: 30-Oct-2025

Relations

• Revised: ISO/IEC 18004:2015 - Information technology - Automatic identification and data capture techniques - QR Code bar code symbology specification
• Effective Date: 10-Aug-2013
• Revises: ISO/IEC 18004:2000 - Information technology - Automatic identification and data capture techniques - Bar code symbology - QR Code
• Effective Date: 15-Apr-2008

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 18004
Second edition
2006-09-01
Information technology — Automatic
identification and data capture
techniques — QR Code 2005 bar code
symbology specification
Technologies de l'information — Techniques d'identification
automatique et de capture des données — Spécification de la
symbologie de code à barres QR Code 2005

Reference number
©
ISO/IEC 2006
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©  ISO/IEC 2006
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ii © ISO/IEC 2006 — All rights reserved

Contents Page
Foreword. vi
Introduction . vi
1 Scope. 1
2 Conformance. 1
3 Normative references. 1
4 Terms and definitions, mathematical and logical symbols, abbreviations and conventions . 2
4.1 Terms and definitions. 2
4.2 Mathematical and logical symbols. 4
4.3 Abbreviations . 4
4.4 Conventions . 5
4.4.1 Module positions . 5
4.4.2 Byte notation . 5
4.4.3 Version references. 5
5 Symbol description. 5
5.1 Basic characteristics. 5
5.2 Summary of additional features . 7
5.3 Symbol structure . 8
5.3.1 Symbol Versions and sizes . 9
5.3.2 Finder pattern. 16
5.3.3 Separator. 17
5.3.4 Timing pattern. 17
5.3.5 Alignment patterns . 17
5.3.6 Encoding region. 17
5.3.7 Quiet zone. 17
6 Requirements. 18
6.1 Encode procedure overview. 18
6.2 Data analysis. 20
6.3 Modes. 20
6.3.1 Extended Channel Interpretation (ECI) mode . 20
6.3.2 Numeric mode. 20
6.3.3 Alphanumeric mode . 20
6.3.4 Byte mode. 20
6.3.5 Kanji mode. 21
6.3.6 Mixing modes. 21
6.3.7 Structured Append mode. 21
6.3.8 FNC1 mode . 21
6.4 Data encoding . 22
6.4.1 Sequence of data . 22
6.4.2 Extended Channel Interpretation (ECI) mode . 23
6.4.3 Numeric mode. 25
6.4.4 Alphanumeric mode . 26
6.4.5 Byte mode. 27
6.4.6 Kanji mode. 29
6.4.7 Mixing modes. 30
6.4.8 FNC1 modes. 30
6.4.9 Terminator. 32
6.4.10 Bit stream to codeword conversion. 33
6.5 Error correction. 37
6.5.1 Error correction capacity . 37
© ISO/IEC 2006 — All rights reserved iii

6.5.2 Generating the error correction codewords. 44
6.6 Constructing the final message codeword sequence. 45
6.7 Codeword placement in matrix. 46
6.7.1 Symbol character representation. 46
6.7.2 Function pattern placement. 46
6.7.3 Symbol character placement. 47
6.8 Data masking. 50
6.8.1 Data mask patterns . 50
6.8.2 Evaluation of data masking results. 53
6.9 Format information . 55
6.9.1 QR Code symbols . 55
6.9.2 Micro QR Code symbols. 56
6.10 Version information . 57
7 Structured Append. 59
7.1 Basic principles. 59
7.2 Symbol Sequence Indicator. 59
7.3 Parity Data. 60
8 Symbol printing and marking . 60
8.1 Dimensions. 60
8.2 Human-readable interpretation. 60
8.3 Marking guidelines. 61
9 Symbol quality. 61
9.1 Methodology. 61
9.2 Symbol quality parameters . 61
9.2.1 Fixed pattern damage . 61
9.2.2 Scan grade and overall symbol grade . 61
9.2.3 Grid non-uniformity . 61
9.3 Process control measurements. 61
10 Decoding procedure overview. 61
11 Reference decode algorithm for QR Code 2005 . 63
12 Autodiscrimination capability. 69
13 Transmitted data . 69
13.1 General principles. 69
13.2 Symbology Identifier. 69
13.3 Extended Channel Interpretations . 69
13.4 FNC1. 70
Annex A (normative) Error detection and correction generator polynomials . 71
Annex B (normative) Error correction decoding steps . 76
Annex C (normative) Format information . 78
C.1 Error correction bit calculation. 78
C.2 Error correction decoding steps . 78
Annex D (normative) Version information . 81
D.1 Error correction bit calculation. 81
D.2 Error correction decoding steps . 81
Annex E (normative) Position of alignment patterns. 83
Annex F (normative) Symbology Identifier . 85
Annex G (normative) QR Code 2005 print quality – symbology-specific aspects. 86
G.1 Fixed Pattern damage. 86
G.1.1 Features to be assessed . 86
G.1.2 Fixed Pattern Damage grading . 88
G.2 Grading of additional parameters . 89
G.2.1 Grading of format information. 89
G.2.2 Grading of version information (QR Code symbols). 91
iv © ISO/IEC 2006 — All rights reserved

G.3 Scan grade. 91
Annex H (informative) JIS8 and Shift JIS character sets . 92
Annex I (informative) Symbol encoding examples . 94
I.1 General. 94
I.2 Encoding a QR Code symbol . 94
I.3 Encoding a Micro QR Code symbol. 96
Annex J (informative) Optimisation of bit stream length . 98
J.1 General. 98
J.2 Optimisation for QR Code symbols . 99
J.3 Optimisation for Micro QR Code symbols . 100
J.3.1 Optimisation principles. 100
J.3.2 Capacity of Micro QR Code symbols. 100
Annex K (informative) User guidelines for printing and scanning of QR Code 2005 symbols. 106
K.1 General. 106
K.2 User selection of error correction level. 106
Annex L (informative) Autodiscrimination. 108
Annex M (informative) Process control techniques . 109
M.1 Symbol Contrast . 109
M.2 Assessing Axial Nonuniformity. 109
M.3 Visual inspection for symbol distortion and defects. 109
M.4 Assessing print growth. 110
Annex N (informative) Characteristics of Model 1 symbols. 111
N.1 Model 1 QR Code symbols . 111
N.1.1 Model 1 overall characteristics . 111
N.1.2 Symbol versions and sizes. 112
N.2 Detailed specifications. 113
Bibliography . 114

© ISO/IEC 2006 — All rights reserved v

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 18004 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 31, Automatic identification and data capture techniques.
This second edition cancels and replaces the first edition (ISO/IEC 18004:2000), which has been technically
revised.
vi © ISO/IEC 2006 — All rights reserved

Introduction
It is necessary to distinguish four technically different, but closely related members of the QR Code family,
which represent an evolutionary sequence.
⎯ QR Code Model 1 was the original specification for QR Code and is described in AIM International
Symbology Specification 97-001.
⎯ QR Code Model 2 was an enhanced form of the symbology with additional features (primarily the addition
of alignment patterns to assist navigation in larger symbols), and was the basis of the first edition of
ISO/IEC 18004.
⎯ QR Code 2005 (the basis of this second edition of ISO/IEC 18004) is closely similar to QR Code Model 2
and, in its QR Code format, differs only in the addition of the facility for symbols to appear in a mirror
image orientation, for reflectance reversal (light symbols on dark backgrounds) and the option for
specifying alternative character sets to the default.
⎯ The Micro QR Code format (also specified in this International Standard), is a variant of QR Code 2005
with a reduced number of overhead modules and a restricted range of sizes, which enables small to
moderate amounts of data to be represented in a small symbol, particularly suited to direct marking on
parts and components, and to applications where the space available for the symbol is severely restricted.
QR Code 2005 is a matrix symbology. The symbols consist of an array of nominally square modules arranged
in an overall square pattern, including a unique finder pattern located at three corners of the symbol (in Micro
QR Code symbols, at a single corner) and intended to assist in easy location of its position, size and
inclination. A wide range of sizes of symbol is provided for, together with four levels of error correction. Module
dimensions are user-specified to enable symbol production by a wide variety of techniques.
QR Code Model 2 symbols are fully compatible with QR Code 2005 reading systems.
Model 1 QR Code symbols are recommended only to be used in closed system applications and it is not a
requirement that equipment complying with this International Standard should support Model 1. Since QR
Code 2005 is the recommended model for new, open systems application of QR Code, this International
Standard describes QR Code 2005 fully, and lists the features in which Model 1 QR Code differs from QR
Code 2005 in Annex N.
© ISO/IEC 2006 — All rights reserved vii

INTERNATIONAL STANDARD ISO/IEC 18004:2006(E)

Information technology — Automatic identification and data
capture techniques — QR Code 2005 bar code symbology
specification
1 Scope
This International Standard defines the requirements for the symbology known as QR Code 2005. It specifies
the QR Code 2005 symbology characteristics, data character encoding methods, symbol formats, dimensional
characteristics, error correction rules, reference decoding algorithm, production quality requirements, and
user-selectable application parameters, and lists in an informative annex the features of QR Code Model 1
symbols which differ from QR Code 2005.
2 Conformance
QR Code 2005 symbols (and equipment designed to produce or read QR Code 2005 symbols) shall be
considered as conforming with this International Standard if they provide or support the features defined in this
International Standard.
Symbols complying with the requirements for QR Code Model 1, as defined in ISO/IEC 18004:2000, may not
be readable with equipment complying with this International Standard.
Symbols complying with the requirements for QR Code Model 2, as defined in ISO/IEC 18004:2000, are
readable with equipment complying with this International Standard.
Reading equipment complying with ISO/IEC 18004:2000 will not be able to read all symbols complying with
this International Standard. Symbols that make use of the additional features of QR Code 2005 will not be
readable by such equipment.
Printing equipment complying with ISO/IEC 18004:2000 will not be able to print all symbols defined in this
International Standard. Symbols that make use of the additional features of QR Code 2005 will not be
printable by such equipment.
It should be noted, however, that QR Code 2005 is the form of the symbology recommended for new and
open systems applications.
3 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO/IEC 8859-1:1998, Information technology — 8-bit single-byte coded graphic character sets — Part 1:
Latin alphabet No. 1
ISO/IEC 15415, Information technology — Automatic identification and data capture techniques — Bar code
print quality test specification — Two-dimensional symbols
© ISO/IEC 2006 — All rights reserved 1

ISO/IEC 15424, Information technology — Automatic identification and data capture techniques — Data
Carrier Identifiers (including Symbology Identifiers)
ISO/IEC 19762-1, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 1: General terms relating to AIDC
ISO/IEC 19762-2, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 2: Optically readable media (ORM)
JIS X 0201, 7-bit and 8-bit coded character sets for information interchange
JIS X 0208:1997, 7-bit and 8-bit double byte coded KANJI sets for information interchange
AIM International Technical Specification, Extended Channel Interpretations:
— Part 1, Identification Schemes and Protocols
— Part 2, Registration Procedure for Coded Character Sets and Other Data Formats
— Character Set Register
AIM International Symbology Specification 97-001, QR Code
GS1 General Specifications, GS1
4 Terms and definitions, mathematical and logical symbols, abbreviations and
conventions
4.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 19762-1 and 19762-2 and the
following apply.
4.1.1
alignment pattern
fixed reference pattern in defined positions in a matrix symbology, which enables the decode software to re-
synchronise the coordinate mapping of the image modules in the event of moderate amounts of distortion of
the image
4.1.2
character count indicator
bit sequence which defines the data string length in a mode
4.1.3
data masking
process of XORing the bit pattern in the encoding region with a data mask pattern to provide a symbol with
more evenly balanced numbers of dark and light modules, and reduced occurrence of patterns which would
interfere with fast processing of the image
4.1.4
data mask pattern reference
three-bit identifier of the data masking patterns applied to the symbol
4.1.5
encoding region
region of the symbol not occupied by function patterns and available for encoding of data and error correction
codewords, and for Version and format information
2 © ISO/IEC 2006 — All rights reserved

4.1.6
exclusive subset
subset of characters within the character set of a mode which are not shared with the more restricted
character set of another mode
4.1.7
Extension Pattern
function pattern in Model 1 symbols, which does not encode data
4.1.8
format information
encoded pattern containing information on symbol characteristics essential to enable the remainder of the
encoding region to be decoded
4.1.9
QR Code
pertaining to QR Code 2005 symbols identified as Versions 1 to 40, as distinct from Micro QR Code symbols
4.1.10
function pattern
overhead component of the symbol (finder, separator, timing patterns, and alignment patterns) required for
location of the symbol or identification of its characteristics to assist in decoding
4.1.11
masking
process of XORing the bit pattern in an area of the symbol with a mask pattern to reduce the occurrence of
patterns which would interfere with fast processing of the image
4.1.12
Micro
pertaining to QR Code 2005 symbols identified as Versions M1 to M4, as distinct from QR Code symbols
4.1.13
mode
method of representing a defined character set as a bit string
4.1.14
mode indicator
four-bit identifier indicating in which mode the following data sequence is encoded
4.1.15
Padding Bit
0 bit, not representing data, used to fill empty positions of the final codeword after the Terminator in a data bit
string
4.1.16
finder pattern
one of three identical components of the finder pattern in QR Code symbols
4.1.17
Remainder Bit
0 bit, not representing data, used to fill empty positions of the symbol encoding region after the final symbol
character, where the area of the encoding region available for symbol characters does not divide exactly into
8-bit symbol characters
4.1.18
Remainder Codeword
pad codeword, placed after the error correction codewords, used to fill empty codeword positions to complete
the symbol if the total number of data and error correction codewords does not exactly fill its nominal capacity
© ISO/IEC 2006 — All rights reserved 3

4.1.19
segment
sequence of data encoded according to the rules of one ECI or encoding mode
4.1.20
separator
function pattern of all light modules, one module wide, separating the finder patterns from the rest of the
symbol
4.1.21
symbol number
three-bit field indicating the symbol version and error correction level applied, used as part of the Format
Information in Micro QR Code symbols
4.1.22
Terminator
bit pattern of defined number (depending on symbol) of all zero bits used to end the bit string representing
data
4.1.23
timing pattern
alternating sequence of dark and light modules enabling module coordinates in the symbol to be determined
4.1.24
Version
size of the symbol represented in terms of its position in the sequence of permissible sizes for Micro QR Code
symbols from 11 × 11 modules (Version M1) to 17 × 17 modules (Version M4) or, for QR Code symbols, from
21 × 21 modules (Version 1) to 177 × 177 (Version 40) modules
NOTE The error correction level applied to the symbol may be suffixed to the version designation, e.g. Version 4-L or
Version M3-Q.
4.1.25
version information
encoded pattern in certain QR Code 2005 symbols containing information on the symbol version together with
error correction bits for this data
4.2 Mathematical and logical symbols
Mathematical symbols used in formulae and equations are defined after the formula or equation in which they
appear.
For the purposes of this document, the following mathematical operations apply.
div is the integer division operator
mod is the integer remainder after division
XOR is the exclusive-or logic function whose output is one only when its two inputs are not equivalent. It is
represented by the symbol ⊕.
4.3 Abbreviations
BCH Bose-Chaudhuri-Hocquenghem
ECI Extended Channel Interpretation
RS Reed-Solomon
4 © ISO/IEC 2006 — All rights reserved

4.4 Conventions
4.4.1 Module positions
For ease of reference, module positions are defined by their row and column coordinates in the symbol, in the
form (i, j) where i designates the row (counting from the top downwards) and j the column (counting from left
to right) in which the module is located, with counting commencing at 0. Module (0, 0) is therefore located at
the upper left corner of the symbol.
4.4.2 Byte notation
Byte contents are shown as hex values.
4.4.3 Version references
For QR Code symbols, symbol versions are referred to in the form Version V-E where V identifies the version
number (1 to 40) and E indicates the error correction level (L, M, Q, H).
For Micro QR Code symbols, symbol versions are referred to in the form Version MV-E where the letter M
indicates the Micro QR Code format and V (with a range of 1 to 4) and E (with values L, M and Q) have the
meanings defined above.
5 Symbol description
5.1 Basic characteristics
QR Code 2005 is a matrix symbology with the following characteristics:
a) Formats:
1) QR Code, with full range of capabilities and maximum data capacity;
2) Micro QR Code, with reduced overhead, some restrictions on capabilities and reduced data capacity
(compared with QR Code symbols).
b) Encodable character set:
1) numeric data (digits 0 - 9);
2) alphanumeric data (digits 0 - 9; upper case letters A -Z; nine other characters: space, $ % * + - . / : );
3) byte data (default: ISO/IEC 8859-1; or other sets as otherwise defined (see 6.3.4));
4) Kanji characters. Kanji characters in QR Code 2005 can be compacted into 13 bits.
c) Representation of data:
A dark module is nominally a binary one and a light module is nominally a binary zero. However, see
5.2 for details of reflectance reversal.
d) Symbol size (not including quiet zone):
1) Micro QR Code symbols: 11 × 11 modules to 17 × 17 modules (Versions M1 to M4, increasing in
steps of two modules per side);
© ISO/IEC 2006 — All rights reserved 5

2) QR Code symbols: 21 × 21 modules to 177 × 177 modules (Versions 1 to 40, increasing in steps of
four modules per side).
e) Data characters per symbol
1) maximum Micro QR Code symbol size, Version M4-L):
⎯ numeric data:  35 characters
⎯ alphanumeric data: 21 characters
⎯ Byte data:  15 characters
⎯ Kanji data:   9 characters
2) maximum QR Code symbol size, Version 40-L:
⎯ numeric data:  7 089 characters
⎯ alphanumeric data: 4 296 characters
⎯ Byte data:  2 953 characters
⎯ Kanji data:  1 817 characters
f) Selectable error correction:
Four levels of Reed-Solomon error correction (referred to as L, M, Q and H in increasing order of
capacity) allowing recovery of:
⎯ L 7%
⎯ M 15%
⎯ Q 25%
⎯ H 30%
of the symbol codewords.
For Micro QR Code symbols, error correction level H is not available. For Version M1 Micro QR Code
symbols, the RS capacity is limited to error detection only.
g) Code type:
Matrix
h) Orientation independence:
Yes (both rotation and reflection)
Figure 1 illustrates a Version 1 QR Code 2005 symbol in normal colour and with reflectance reversal (see 5.2),
in both normal and mirror image orientations.
Figure 2 illustrates a Version M2 Micro QR Code symbol in normal colour and with reflectance reversal (see
5.2), in both normal and mirror image orientations.
6 © ISO/IEC 2006 — All rights reserved

5.2 Summary of additional features
The use of the following additional features is optional in QR Code 2005:
⎯ Structured append
This allows files of data to be represented logically and continuously in up to 16 QR Code 2005 symbols.
These may be scanned in any sequence to enable the original data to be correctly reconstructed.
Structured Append is not available with Micro QR Code symbols.
⎯ Extended Channel Interpretations
This mechanism enables data using character sets other than the default encodable set (e.g. Arabic,
Cyrillic, Greek) and other data interpretations (e.g. compacted data using defined compression schemes)
or other industry-specific requirements to be encoded. Extended Channel Interpretations other than the
default interpretation are not available in Micro QR Code symbols.
⎯ Reflectance reversal
Symbols are intended to be read when marked so that the image is either dark on light or light on dark
(see Figures 1 and 2). The specifications in this International Standard are based on dark images on a
light background, therefore in the case of symbols produced with reflectance reversal references to dark
or light modules should be taken as references to light or dark modules respectively.
⎯ Mirror imaging
The arrangement of modules defined in this International Standard represents the "normal" orientation of
the symbol. It is, however, possible to achieve a valid decode of a symbol in which the arrangement of the
modules has been laterally transposed. When viewed with the finder patterns at the top left, top right and
bottom left corners of the symbol, the effect of mirror imaging is to interchange the row and column
positions of the modules.
Figure 1 — Examples of QR Code 2005 symbol encoding the text "QR Code Symbol" – (a) normal
orientation and normal reflectance arrangement; (b) normal orientation and reversed reflectances; (c)
mirror image orientation and normal reflectance arrangement; (d) mirror image orientation and
reversed reflectances
© ISO/IEC 2006 — All rights reserved 7

Figure 2 — Examples of Version M2 Micro QR Code symbol encoding the text "01234567" – (a) normal
orientation and normal reflectance arrangement; (b) normal orientation and reversed reflectances; (c)
mirror image orientation and normal reflectance arrangement; (d) mirror image orientation and
reversed reflectances
NOTE The corner marks in Figures 1 and 2 indicate the extent of the quiet zone.
5.3 Symbol structure
Each QR Code 2005 symbol shall be constructed of nominally square modules set out in a regular square
array and shall consist of an encoding region and function patterns, namely finder, separator, timing patterns,
and alignment patterns. Function patterns do not encode data. The symbol shall be surrounded on all four
sides by a quiet zone border. Figure 3 illustrates the structure of a Version 7 symbol. Figure 4 illustrates the
structure of a Version M3 symbol.

QUIET ZONE
FINDER PATTERN
SEPARATOR
FUNCTION
PATTERNS
TIMING PATTERNS
ALIGNMENT PATTERNS
FORMAT INFORMATION
ENCODING
VERSION INFORMATION
REGION
DATA AND
ERROR
CORRECTION
CODEWORDS
Figure 3 — Structure of a QR Code 2005 symbol
8 © ISO/IEC 2006 — All rights reserved

Figure 4 — Structure of Version M3 Micro QR Code symbol
5.3.1 Symbol Versions and sizes
5.3.1.1 QR Code symbols
There are forty sizes of QR Code 2005 symbol referred to as Version 1, Version 2 . Version 40. Version 1
measures 21 modules × 21 modules, Version 2 measures 25 modules × 25 modules and so on increasing in
steps of 4 modules per side up to Version 40 which measures 177 modules × 177 modules. Figures 5 to 10
illustrate the structure of Versions 1, 2, 6, 7, 14, 21 and 40.
© ISO/IEC 2006 — All rights reserved 9

Data and EC Codewords
Format information and its
error correction code
Version information and its
error correction code
Remainder bits
25 modules
21 modules
modules
modules
Version 1 Version 2
Figure 5 — Version 1 and 2 symbols

10 © ISO/IEC 2006 — All rights reserved

41 modules
modules
Version 6
Figure 6 — Version 6 symbol
© ISO/IEC 2006 — All rights reserved 11

45 modules
modules
Version 7
Figure 7 — Version 7 symbol
12 © ISO/IEC 2006 — All rights reserved

73 modules
modules
Version 14
Figure 8 — Version 14 symbol
© ISO/IEC 2006 — All rights reserved 13

101modules
modules
Version 21
Figure 9 — Version 21 symbol
14 © ISO/IEC 2006 — All rights reserved

177m odules
modules
Version 40
Figure 10 — Version 40 symbol
5.3.1.2 Micro QR Code symbols
There are four sizes of Micro QR Code symbol, referred to as Versions M1 to M4. Version M1 measures
11 × 11 modules, Version M2 13 × 13 modules, Version M3 15 × 15 modules, and Version M4 17 × 17
modules, i.e. increasing in steps of 2 modules per side. Figure 11 illustrates the structure of Micro QR Code
Versions M1 to M4.
NOTE Two formats of M3 symbol are shown, which differ only in the codeword placement according to the error
correction level.
© ISO/IEC 2006 — All rights reserved 15

Figure 11 — Versions of Micro QR Code symbol
5.3.2 Finder pattern
5.3.2.1 QR Code symbols
There are three identical Finder Patterns located at the upper left, upper right and lower left corners of the
symbol respectively as illustrated in Figure 3. Each finder pattern may be viewed as three superimposed
concentric squares and is constructed of dark 7 × 7 modules, light 5 × 5 modules and dark 3 × 3 modules. The
ratio of module widths in each finder pattern is 1 : 1 : 3 : 1 : 1 as illustrated in Figure 12. The symbol is
preferentially encoded so that similar patterns have a low probability of being encountered elsewhere in the
symbol, enabling rapid identification of a possible QR Code 2005 symbol in the field of view. Identification of
t
...