ISO/IEC 9995 Information technology — Keyboard layouts for text and office systems is an ISO/IEC standard series defining layout principles for computer keyboards. It provides the base for national and industry standards which define such layouts.
The project of this standard was adopted by ISO in 1985 under the proposition of Dr Yves Neuville. The ISO/IEC 9995 standard series dates back to 1994 and has undergone several updates over the years. The last major revision was published in December 2025 and January 2026.
Parts
The ISO/IEC 9995 standard series currently (as of February 2026) consists of the following parts: ISO/IEC 9995-1:2026 General principles governing keyboard layoutsISO/IEC 9995-1:2026 Information technology — Keyboard layouts for text and office systems — Part 1: General principles governing keyboard layouts ISO/IEC 9995-2:2026 Alphanumeric sectionISO/IEC 9995-2:2026 Information technology — Keyboard layouts for text and office systems — Part 2: Alphanumeric section ISO/IEC 9995-3:2026 Latin International keyboard layoutISO/IEC 9995-3:2026 Information technology — Keyboard layouts for text and office systems — Part 3: Latin International keyboard layoutThe content of this part has completely changed compared to its predecessor version:ISO/IEC 9995-3:2010 Complementary layouts of the alphanumeric zone of the alphanumeric sectionISO/IEC 9995-3:2010 Information technology — Keyboard layouts for text and office systems — Part 3: Complementary layouts of the alphanumeric zone of the alphanumeric section — Withdrawn (Edition 3, 2010) ISO/IEC 9995-4:2025 Numeric sectionISO/IEC 9995-4:2025 Information technology — Keyboard layouts for text and office systems — Part 4: Numeric section ISO/IEC 9995-5:2009 Editing and function sectionISO/IEC 9995-5:2009 Information technology — Keyboard layouts for text and office systems — Part 5: Editing and function section ISO/IEC 9995-6:2006 Function section (withdrawn) ISO/IEC 9995-7:2009 Symbols used to represent functionsISO/IEC 9995-7:2009 Information technology — Keyboard layouts for text and office systems — Part 7: Symbols used to represent functions with Amendment 1 (2012)ISO/IEC 9995-7:2009/Amd 1:2012 Information technology — Keyboard layouts for text and office systems — Part 7: Symbols used to represent functions — Amendment 1As of February 2026, this part is under revision, and a new version is expected. ISO/IEC 9995-8:2009 Allocation of letters to the keys of a numeric keypadISO/IEC 9995-8:2009 Information technology — Keyboard layouts for text and office systems — Part 8: Allocation of letters to the keys of a numeric keypad ISO/IEC 9995-9:2026 Groups and mechanisms for multilingual and multiscript inputISO/IEC 9995-9:2026 Information technology — Keyboard layouts for text and office systems — Part 9: Groups and mechanisms for multilingual and multiscript input ISO/IEC 9995-10:2025 Conventional symbols and methods to represent graphic characters not uniquely recognizable by their glyph on keyboards and in documentationISO/IEC 9995-10:2025 Information technology — Keyboard layouts for text and office systems — Part 10: Conventional symbols and methods to represent graphic characters not uniquely recognizable by their glyph on keyboards and in documentation ISO/IEC 9995-11:2026 Functionality and labelling of dead keysISO/IEC 9995-11:2026 Information technology — Keyboard layouts for office systems — Part 11: Functionality and labelling of dead keys ISO/IEC 9995-12:2020 Keyboard group selectionISO/IEC 9995-12:2020 Information technology — Keyboard layouts for text and office systems — Part 12: Keyboard group selection
The parts ISO/IEC 9995-5, ISO/IEC 9995-8, and ISO/IEC 9995-12 were not affected by the revision of the ISO/IEC 9995 series published in 2025/2026.
The part ISO 9995-6:2006 Function section was withdrawn in October 2009, as its content was integrated into ISO/IEC 9995-5:2009 Editing and function sectionISO catalogue - ISO/IEC 9995-6:2006 (whose prior version was titled ISO/IEC 9995-5:2006 Editing sectionISO catalogue - ISO/IEC 9995-5:2006).
Part 1: "General principles governing keyboard layouts"
ISO/IEC 9995-1:2026 provides a fundamental description of keyboards suitable for text and office systems, and defines several terms which are used throughout the ISO/IEC 9995 standard series.
Physical division and reference grid
The figure shows the division of a keyboard into sections, which are subdivided into zones. alphanumeric section alphanumeric zone (indicated by green coloring) function zones (indicated by light purple coloring) numeric section numeric zone (indicated by darker red coloring) function zone (indicated by lighter red coloring) editing and function section (in fact covering all parts of the keyboard which do not belong to the alphanumeric or numeric section) cursor key zone (indicated by darker grey coloring) editing function zone (indicated by lighter grey coloring) The presence of a numeric section is not required by the standard. Also, the standard does not prevent a numeric section from being placed left of the alphanumeric section.
By means of the reference grid, each key can be identified by a unique combination of a letter (indicating the row) and a sequence of two digits (indicating the column). E.g., the key visually marked as "1" on several layouts is identified as "Key E01". The labeling rules do allow for function keys to be arranged in a position other than above the alphanumeric section, or to be arranged in more than one row (thus, e.g. an AT keyboard is compliant to the standard): Columns containing editing or function keys are to be numbered from 60 on when placed beyond a right numeric section, or from 80 downwards when placed to the left of the alphanumeric section. Rows above the alphanumeric section are to be labeled from K on, and rows below the space key are to be labeled from Z downwards. The grid may be angled (as shown in the figure within the alphanumeric section), or squared (thus, keyboards where the alphanumeric keys are ordered in pure vertical columns are compliant to the standard).
The standard does not constrain the numbers of rows and columns in the alphanumeric section.
Levels and groups
The selection of level and group during the input of a character (e.g. by means of a shift key, an AltGr key, or a group selection key or key sequence) is specified in ISO/IEC 9995-2.
Levels ("unshifted" "shifted", "AltGr", "AltGr+Shift")
The characters which can be input by the keys in the alphanumeric section usually are organized in levels. For two-cased scripts like Latin, the basic level ("Level 1") contains lower-case letters, while the "Level 2" contains capital letters (therefore, these levels are usually called "unshifted" and "shifted"). For characters which are not letters (like punctuation marks), no rules are given regarding their distribution among the levels. While digits are commonly in Level 1, there are exceptions (e.g. the French keyboard layout).
The standard allows for up to four levels. Characters in the third level usually (but not mandatory by the standard) are selected by means of an AltGr key. Characters in the fourth level usually are selected by pressing them together with an AltGr key and a Shift key. Unless a dedicated key or key combination (like pressing and releasing it before entering the key whose fourth level character is to be input, resembling a sticky key feature) exists, this could require an uncomfortable "guitar chord grip" using three fingers simultaneously. Therefore, the fourth level should only be used for obscure or rarely used characters or other specific cases.ISO/IEC 9995-1:2026 section 4.2.3 Usage of Level 4 Its characters do not need to be shown on the keytops, but only in instruction documents for the specific keyboard layout.ISO//IEC 9995-1:2026 clause 4.2.3 Usage of Level 4, Note 1: "Allocating ... rarely used characters. In this case, the character needs not to be engraved on the keytop, but only shall be listed in the layout definition and should be mentioned in manuals."
Groups If the organization into three or four levels is not sufficient or considered appropriate to accommodate all characters to be contained in a specific layout, then "groups" may be defined, which then constitute a higher hierarchical unit than levels. Thus, each such group is usually subdivided into up to four levels. Common examples are layouts allowing the input of characters of different scripts. On the Japanese keyboard layout, the kana constitutes the second group. The Canadian Québec layout (1992) and the German E1 layout (2018, updated 2023) allow the input of considerably more characters than their preceding editions, to overcome the historic limits of mechanical typewriters.
Mechanisms to switch between groups are provided in ISO/IEC 9995-2, ISO/IEC 9995-9, and ISO/IEC 9995-12.
"Extra characters" and "Extra selector"
If characters contained in a "secondary group" are a supplement of the "primary group" (rather than being characters of a different script), this secondary group may be called "extra characters".ISO/IEC 9995-2:2026 Information technology — Keyboard layouts for text and office systems — Part 2: Alphanumeric section, section 7.3.7 Group select, Group 2 select and Group 2 single-select Then, a "group 2 single-select" key or key combination (as defined in ISO/IEC 9995-2) causes only the next key actuation to yield the character of the secondary group, while the system switches back to the primary group after that. Such a key or key combination may be named "Extra selector". The keyboard symbol for this function is or , depending on whether the characters of the secondary group are shown on the whole right part or on the top right part of the keytop. The German extended layout E1 uses as a variant of the latter symbol, as the key combination there is named "" (German for "extra selector").
Depictions on the keytops ISO/IEC 9995-1:2026 specifies three ways of key labelling and symbol positioning: columnar placement, group-1-priorized placement, level-4-including placement.
Columnar placement
Here, the level is indicated by the row where the character is depicted on the keytop: Level 2 ("shifted") above of Level 1 ("unshifted") Level 3 ("AltGr") below Level 1 ("unshifted"). The group is indicated by the column on the keytop: The first or "primary group" at the left keytop border The second or "secondary group" at the right keytop border Additional groups (if existing) in between. When letters on a case pair are associated with a key, only the capital character needs to be shown on the keytop for the primary group, while the lowercase character only is shown for the secondary group.
Thus, on the depicted key of the German T2 layout (which is outdated since 2018), in the primary group are the characters in Level 1 (unshifted), in Level 2 (shifted), and in Level 3 (accessed by the AltGr key). In the secondary group, there is the lowercase letter in Level 1 (unshifted) and its capital counterpart in Level 2 (shifted).
In prior editions of the standard, this was the only way specified in there. As for stacking three characters on a keytop, the symbols have to be small enough, which posed problems regarding legibility. Therefore, the other two ways were developed. However, prior editions described the possibility to place Level 3 characters on the front of the keycaps. As keyboards produced since the 2020s predominantly have flat keys without providing enough space for readable symbols on the front, this possibility was dropped in the revision published 2026.
Group-1-priorized placement